mjhjmtu

I want to reproduce the following figure with tikz (because there is a typo in the text in this figure).

My tikz code is (borrowed from here)

documentclass[tikz,border=10pt]standalone
usetikzlibrarydecorations.text
definecolormygrayRGB208,208,208
definecolormymagentaRGB226,0,116
newcommand*mytextstylesffamilyLargebfseriescolorblack!85
newcommandarcarrow[3]%
 % inner radius, middle radius, outer radius, start angle,
 % end angle, tip protusion angle, options, text
 pgfmathsetmacrorin1.7
 pgfmathsetmacrormid2.2
 pgfmathsetmacrorout2.7
 pgfmathsetmacroastart#1
 pgfmathsetmacroaend#2
 pgfmathsetmacroatip5
 fill[mygray, very thick] (astart+atip:rin)
 arc (astart+atip:aend:rin)
 -- (aend-atip:rmid)
 -- (aend:rout) arc (aend:astart+atip:rout)
 -- (astart:rmid) -- cycle;
 path[
 decoration = 
 text along path,
 text = mytextstyle,
 text align = align = center,
 raise = -1.0ex
 ,
 decorate
 ](astart+atip:rmid) arc (astart+atip:aend+atip:rmid);


begindocument

begintikzpicture
 fill[even odd rule, mymagenta] circle (1.5);

 node at (0,0) [
 font = mytextstyle,
 color = white,
 align = center
 ]
 Learn\
 $6sigma$
 ;

 arcarrow 853Define
 arcarrow290357Measure
 arcarrow210289Analyze
 arcarrow206146Improve
 arcarrow13096Control

endtikzpicture

enddocument

and the output is

I need hints to get my figure more close the original one. Thanks

It is certainly possible to draw something of this sort. (I did not attempt to match the colors. UPDATE: corrected the orientation of the lower-most text, big thanks to manooooh!)

documentclass[tikz,border=3.14mm]standalone
usepackagetextgreek
usetikzlibrarydecorations.text,arrows.meta,bending
begindocument
begintikzpicture
newcommandLineWidth10mm
newcommandRadius3cm
node[font=sffamilybfseries,scale=3.4,anchor=south] at (0,-0.1) LEARN;
node[font=sffamily,scale=6,anchor=north] at (0,0.5) 6textsigma;
foreach X [count=Y] in yellow!50!orange,gray!50,cyan!50,gray,red
draw[line width=LineWidth,X] (90-(Y-1)*72:Radius)
 arc(90-(Y-1)*72:90-(Y)*72:Radius);

foreach X [count=Y] in yellow!50!orange,gray!50,cyan!50,gray,red
draw[-Triangle[bend,length=0.75*LineWidth,width=1.5*LineWidth],
line width=LineWidth,X] 
(90-(Y-0.5)*72:Radius)
 arc(90-(Y-0.5)*72:90-(Y)*72-10:Radius);

foreach X [count=Y] in Define,Measure,Analyze,Improve,Control 
ifnumY=3
fill[decoration=text along path, text= X,
 raise=-3pt,text color=white,text align=center,decorate] 
 (90-(Y)*72:Radius)
 arc(90-(Y)*72:90-(Y-1)*72:Radius);
else
fill[decoration=text along path, text= X,
 raise=-3pt,text color=white,text align=center,decorate] 
 (90-(Y-1)*72:Radius)
 arc(90-(Y-1)*72:90-(Y)*72:Radius);
fi 

endtikzpicture
enddocument

ADDENDUM FOR FUN: I was trying to make the corners of the arrow path round. One can design arbitrary arrows with pgfdeclarearrow, and the basis of my attempt is the example on p. 1096 of the pgfmanual. I could, however, not make pgfsetcornersarced work. (If I would have to guess, I'd probably say that this is because the examples on pp. 1069 of the pgfmanual use pgfusepathstroke, the analogon of which is pgfusepathfill. However, this is not allowed in a arrow declaration, where one has to use the quick version pgfusepathqfill, which, according to what I found, ignores pgfsetcornersarced.) But @circumscribe has a much better solution, which I shamelessly copy here. The only minor improvement (?) is that I move the texts a bit away from the arrow heads, but full credits go to @circumscribe.

documentclass[tikz,border=3.14mm]standalone
usepackagetextgreek
usetikzlibrarydecorations.text,arrows.meta,bending
pgfdeclarearrow
 name =rtriangle,
 parameters = thepgfarrowlength ,
 setup code = 
 % The different end values:
 pgfarrowssettipend.25pgfarrowlength
 pgfarrowssetlineend-.25pgfarrowlength
 pgfarrowssetvisualbackend-.5pgfarrowlength
 pgfarrowssetbackend-.75pgfarrowlength
% The hull
pgfarrowshullpoint.5pgfarrowlength0pt
pgfarrowshullpoint-.5pgfarrowlengthpgfarrowlength
pgfarrowshullpoint-.5pgfarrowlength-pgfarrowlength % Saves: Only the length:
 pgfarrowssavethepgfarrowlength
 ,
 drawing code = 
 pgfsetroundjoin
 pgfsetlinewidth.2pgflinewidth
 pgfpathmovetopgfqpoint.5pgfarrowlength0pgfarrowlength
 pgfpathlinetopgfpoint-.5pgfarrowlengthpgfarrowlength
 pgfpathlinetopgfqpoint-.5pgfarrowlength-pgfarrowlength
 pgfpathclose
 pgfusepathqfillstroke
,
 defaults = length = 4cm 

begindocument
begintikzpicture
newcommandLineWidth10mm
newcommandRadius3cm
node[font=sffamilybfseries,scale=3.4,anchor=south] at (0,-0.1) LEARN;
node[font=sffamily,scale=6,anchor=north] at (0,0.5) 6textsigma;
foreach X [count=Y] in yellow!50!orange,gray!50,cyan!50,gray,red
draw[line width=LineWidth,X] (90-(Y-1)*72:Radius)
arc(90-(Y-1)*72:90-(Y)*72:Radius);
%`,width=1.5*LineWidth
foreach X [count=Y] in yellow!50!orange,gray!50,cyan!50,gray,red
draw[-rtriangle[bend,length=0.65*LineWidth],
line width=LineWidth,X]
(90-(Y-0.5)*72:Radius)
arc(90-(Y-0.5)*72:90-(Y)*72-10:Radius);

foreach X [count=Y] in Define,Measure,Analyze,Improve,Control
ifnumY=3
fill[decoration=text along path, text= X,
 raise=-3pt,text color=white,text align=center,decorate]
 (90-(Y)*72-5:Radius)
arc(90-(Y)*72-5:90-(Y-1)*72-5:Radius);
else
fill[decoration=text along path, text= X,
 raise=-3pt,text color=white,text align=center,decorate]
 (90-(Y-1)*72-5:Radius)
arc(90-(Y-1)*72-5:90-(Y)*72-5:Radius);
fi 

endtikzpicture
enddocument

P.S. As for the question whether "LEAN" or "LEARN" is correct, I really don't now. However, "lean" does not sound right to marmots (a lean marmot won't survive the winter). So I kept "learn". ;-)

Here's an augmented version of marmot's answer, per his request.

The main improvement is the arrowheads, which now have rounded corners.
I'm using a custom arrowhead for this because the Triangle[round,line width=0pt .1] arrowhead is unfortunately disconnected from its shaft if the head is relatively small in comparison to the line width (as it is in this case). (And also because marmot asked for it.)

Arrowheads with rounded corners can be declared with pgfdeclarearrow by setting a positive line width with pgfsetlinewidth<radius>, calling pgfsetroundjoin and stroking the path tracing out the arrowhead in addition to filling it with pgfusepathqfillstroke. This can be seen in the preamble below.
More information about declaring arrow tips can be found in the pgf manual (§104.4 on p1093 as of this writing, §100.4 on p1017 before 05 jan 2019), but I would also highly recommend taking a look at the source of the arrows.meta library to see some examples.

Here's the result:

documentclass[tikz,border=2.718281828mm]standalone

usepackagetextgreek
usetikzlibrarydecorations.text,arrows.meta,bending

pgfdeclarearrow
 name = mytriangle,
 parameters = thepgfarrowlength, thepgfarrowwidth, thepgfarrowlinewidth, ifpgfarrowroundcap cfi ,
 defaults = length = 0pt .85, width = 0pt 1.3, line width = 0pt .1, round = true ,
 setup code = 
 %% The different end values:
 pgfarrowssettipend1pgfarrowlength
 pgfarrowssetlineend.2pgfarrowlength
 pgfarrowssetvisualbackend0pgfarrowlength
 pgfarrowssetbackend0pgfarrowwidth
 %% The hull:
 pgfarrowshullpoint1pgfarrowlength0pgfarrowwidth
 pgfarrowsupperhullpoint0pgfarrowlength.5pgfarrowwidth
 %% Values that are used when drawing:
 pgfarrowssavethepgfarrowwidth
 pgfarrowssavethepgfarrowlength
 pgfarrowssavethepgfarrowlinewidth
 ,
 drawing code = 
 ifpgfarrowroundcappgfsetroundjoinfi
 pgfsetlinewidthpgfarrowlinewidth
 pgfpathmovetopgfqpoint1pgfarrowlength0pgfarrowwidth
 pgfpathlinetopgfpoint0pgfarrowlength.5pgfarrowwidth
 pgfpathlinetopgfqpoint0pgfarrowlength-.5pgfarrowwidth
 pgfpathclose
 pgfusepathqfillstroke
 ,


definecolormyredrgb.92,.26,.23
definecolormyyellowrgb.97,.69,.21
definecolormygrayrgb.54,.53,.55
definecolormycyanrgb.38,.66,.65
definecolormybluergb.07,.24,.32

begindocument

begintikzpicture
 newcommand*LineWidth1.2cm
 newcommand*Radius3cm
 %% Text:
 node[font=sffamilybfseries,scale=3.4,anchor=south,color=myblue] at (0,-0.1) LEAN;
 node[font=sffamily,scale=6,anchor=north,color=myblue] at (0,0.5) 6textsigma;
 %% Arrows:
 foreach X [count=Y] in myyellow,myred,myblue,mycyan,mygray 
 draw[-mytriangle,line width=LineWidth,X,rotate=72*(Y-1)]
 (100:Radius) arc (100:5:Radius);
 
 %% One arrowhead needs to be redrawn because it is covered
 draw[-mytriangle,line width=LineWidth,myyellow]
 (45:Radius) arc (45:5:Radius);
 %% Text on arrows:
 foreach X/reverse [count=Y] in Define/true,Control/true,Improve/false,Analyze/false,Measure/false 
 path[rotate=72*(Y-1),decorate,decoration=text along path,text=X,
 raise=-2.5pt,text color=white,text align=center,reverse path=reverse]
 (52-36:Radius) arc(52-36:52+36:Radius);
 
endtikzpicture

enddocument

Note that I've used the reverse path key to flip "Define" and "Control" and am using the rotate key to rotate the arrows by multiples of 72 º instead performing these computations inside the draw command. One arrowhead is drawn twice because they form circle and one of them will thus always be at the bottom.

Here is a version that uses the round version of the Triangle arrowhead.
Because this arrowhead is partially disconnected from its shaft if it only extends a little at the sides I'm drawing the arrowheads separately from the shafts, which also fixes the overlap problem.

The result is mostly identical:

documentclass[tikz,border=2.718281828mm]standalone

usepackagetextgreek
usetikzlibrarydecorations.text,arrows.meta,bending

tikzsetmytriangle/.tip=Triangle[length = 0pt .95,width=0pt 1.45,round,line width=0pt .1]

definecolormyredrgb.92,.26,.23
definecolormyyellowrgb.97,.69,.21
definecolormygrayrgb.54,.53,.55
definecolormycyanrgb.38,.66,.65
definecolormybluergb.07,.24,.32

begindocument

begintikzpicture
 newcommand*LineWidth1.2cm
 newcommand*Radius3cm
 %% Text:
 node[font=sffamilybfseries,scale=3.4,anchor=south,color=myblue] at (0,-0.1) LEAN;
 node[font=sffamily,scale=6,anchor=north,color=myblue] at (0,0.5) 6textsigma;
 %% Arrow shafts:
 foreach X [count=Y] in myyellow,myred,myblue,mycyan,mygray 
 draw[line width=LineWidth,X,rotate=72*(Y-1)]
 (95:Radius) arc (95:20:Radius);
 
 %% Arrowheads
 foreach X [count=Y] in myyellow,myred,myblue,mycyan,mygray 
 draw[-mytriangle,line width=LineWidth,X,rotate=72*(Y-1)]
 (35:Radius) arc (35:5:Radius);
 
 %% Text on arrows:
 foreach X/reverse [count=Y] in Define/true,Control/true,Improve/false,Analyze/false,Measure/false 
 path[rotate=72*(Y-1),decorate,decoration=text along path,text=X,
 raise=-2.5pt,text color=white,text align=center,reverse path=reverse]
 (52-36:Radius) arc(52-36:52+36:Radius);

 
endtikzpicture

enddocument