People who reuse variables.
Yeah, sure, let's just go declare
number1 = g * 86;
Oh and 10 lines down let's reset it
number1 = 0;
I WILL FIND YOU. I WILL DESTROY YOUR SMALL RAM 'ed THING YOU CALL YOUR COMPUTER.
Variables should be made for one purpose and one purpose only.

They heard of this thing called reusing code 😂

If the variable is still in scope, it likely will decrease the size if the executable as instead if allocating the space for both variables it only needs the space for one. Size could be trivial in YOUR application and it makes it unreadable, but your statement is context specific.