Look at the enclosed 2 pictures:


One is 5/50 4*, other is 4/55 5*. As you can see, 4* has more potent sig, even tho he is one rank lower and 20 sigs behind the 5*. Same case is CapIW for example.
I am not protesting, I just don't know why is it this way? 4* sigs are much more available, so why does 5* sig level scale worse, when the stones are less available. Could please anyone explain this to me?
Also before anyone says it, I am fully aware that 5* sigs are easily accessible nowadays and it is no problem to get them and pump them into champions.