You didn't give enough information for us to tell you whether the chart is correct, but if it is correct it might be explained by blocker effects.
Ie: Your opponent's bet/fold range contains a lot of 9s, 8s and 7s, so your jam gets called less often when you jam with 44 compared to when you jam with 99, 88 or 77.
> Originally posted by OP:> I can't see any reason to shove 44 but always fold 99 88 77What stack depth is this for? Because at certain depths like 12-15bb it actually makes sense. 44 is pure shove because you need fold equity and it plays terribly in a called pot. 99/88/77 at that same depth might have enough equity to flat or 3bet smaller since they actually flop well and aren't purely relying on everyone folding. The chart is probably fine, just context-dependent.
