They really should. I've been programming over 20 years and don't think I've seen a program without at least a few defects. A couple have come close, those are impressive, but bugs always happen.
Even most Hello Worlds don't check the pipe was written to correctly. And now we get into "well actually that's technically not a bug because it is not in the spec" and if we're finding the need to split that hair, we can hardly be talking about some mythically perfect software.
"Every program has at least one bug and can be shortened by at least one instruction -- from which, by induction, one can deduce that every program can be reduced to one instruction which doesn't work."
“The reward for coding errors found in Knuth's TeX and Metafont programs (as distinguished from errors in Knuth's books) followed an audacious scheme inspired by the wheat and chessboard problem,[10] starting at $2.56, and doubling every year until it reached $327.68.”
They're features!
The word for this is not "perfect", but "overengineered"