This is roughly what happens, but you shouldn't attribute this to rudeness. Compiler users also demand performance. They compare implementations (and languages)

This is roughly what happens, but you shouldn't attribute this to rudeness. Compiler users also demand performance. They compare implementations (and languages) and point out when such-and-such is X% slower. They file bugs about "missed" optimizations and "unnecessary" instructions. C is especially awkward here, because compilers are expected to precisely conform the C specification, but at the same time C users don't actually want to program for the abstract machine from the C specification (the one that can't overflow signed integers or shift by a full int width). C users expect their programs to actually behave like programs for a particular hardware they target, without any overhead or discrepancy from "emulating" the imaginary C-spec machine. In face of such conflicting requirements, C compilers will always be forced to balance performance, predictability, conformance, and compatibility.