In Klingon society, honor is basically a political talking point, like 'Family values'. Politicians score points with their constituents by saying 'You are better than those people over there because you have honor and they don't', they idolize a fictitious past where everybody had honor, then they ignore it and do whatever they want. Just like family values.
There are a handful of people like Worf who are really principled and take it very seriously. But also like in the real world, people like that are also more flexible when they see somebody they care about is getting hurt.
Honor does require victory, but not all victory is honorable. A straight up military victory is honorable, but secretly poisoning somebody or using sneaky financial tricks is not.