Electrical panel question

It's not just Zinsco and Pacific. In the early 90's I worked for a local Lennox dealer. One of the boss's son's just bought a nice manufactured home. This is not a trailer. All electric house, one of the box breakers failed for "I forget" I think the dryer? The finger contacts on the breaker that engaged the buss failed. That whole deal should have been recalled.
I have a few that failed in the same way. Trying to transfer the big loads to new distribution panel.