Identifying and Fixing Bench Press Weak Points

I tried to search for this question and perhaps I wasn’t using the correct verbiage. I’m trying to figure out where I’m weak in the flat bench press so I can improve that. How do you identify where your weak points are? Yes form is the common one and I’m working on that by watching video’s, especially Dave Tate’s Bench Press Cure video.

Is it as simple as if you can pass the midway point and lockout the issue is with the triceps? Or if you can’t get it off your chest it’s your pectorals?

Once you’ve identified which body part is the problem, what are some of the better exercises to help improve those points?

Pm me so I can get the video