If the crew think "we've got this", then they see no reason to perform a go around. I think the problem is that it can very difficult to take a mental step back, and objectively assess your own performance. Ideally, the PM performs this role, but the PM can be as much "in the loop" as the PF. This psychology affects all teams of people, in any discipline. People assigned to monitor can become too closely involved in the execution of the task.
Trained procedures and SOPs help the crew to assess their performance, but when you go outside that envelope you can also lose the awareness and ability to recognise that you are dangerously outside the envelope.