Blockchain Trilemma: Does anyone have an example of compromising security to improve decentralization and scalability?

I understand how you can compromise on decentralization or scalability, but is there any real world examples where security was compromised to get the other 2?

It seems to me that compromising on decentralization is implicitly a compromise on security, but maybe it's just that security is a must-have, so you either compromise on scalability or decentralization.

If I had to classify rollups, they compromise on decentralization outside of L1 to perform more transactions and contract executions faster, but are required to prove to the decentralized L1 network they executed accurately in order to cement their previously relatively centralized actions onto L1.