All of my co-workers are good programmers. But some are good programmers who care about invariants and others are good programmers who will trample invariants

All of my co-workers are good programmers. But some are good programmers who care about invariants and others are good programmers who will trample invariants to get this week's feature done. I think it is really a matter of process. E.g. code reviews. But I don't yet know how to strike the balance between rigour and efficiency.