Never mind "try not to pay", that's table stakes. Likelier than not, they'll seek some form of reparation.

Sounds like having to pay even if Mozilla terminated it was built in.

Wow. Whoever managed to get that clause in there must be pretty happy right now.

Or maybe Mozilla doesn't want to send search queries and user info to Verizon for analytics. Plus there might be a trust issue with search results.

That's not an "or". According to the article, Mozilla is very likely still entitled to payment after terminating. The statement from Yahoo in the grandparent comment makes it sound like Verizon didn't quite realise this possibility and are looking to avoid it.