I like maximum compile-time verification, code contracts, quick and "noisy" failures, and strictness in accepted inputs.

"Be lenient in what you accept and discard faulty inputs silently" is the opposite of my programming ideology.

"Trust your colleague to not violate your contracts" is also not about me; in fact I don't even trust myself with "violatable" contracts. Hence I like bullet-proof code whenever at all possible, even if modern languages are a bit lacking in making this possible.