i always get to repair destrier,so i dont use it. You were unlucky i guess. I figured that if you use katana as example for few maps,and then you change katana to other item be shure that item is gona get broken if it is expencive. Only way to fool repairs is to use same gear all the time or change gear every round or get out of server if you see your team is gonna lose. 
I sometimes leave server or change banner to avoid repairs.
I don't believe any of these methods actually work, aside from leaving the server before the end of the round, which I'm fairly certain is bannable if you do it repeatedly.
Each tick at the same time you get money there's a random chance your gear will break, so longer rounds = more chance for broken gear. Higher WPF has a slight effect on this for weapons, but not a massive one.
If you have a certain item that seems to break a lot, it's just bad luck. It happens, and is why you need to have some reserve cash on hand for when you get unlucky. As long as your gear costs are in the 30-35k range you should be fine.
