Core processor New gen vs old gen?

So apparently this has been giving me headaches for weeks
If an i5 is faster than an i3 and the i7 is faster than all of them and then the new gen i3 is faster than and i5 and the new gen i5 is faster than an i7 and sooo on
My question is then why are they not releasing and i3 with 1st gen 2nd gen 3rd gen 4th gen and soo on rather than confusing with i5 and i7 or just release an i9 and later an i11 rather than releasing gens on specific processors?