Missing 1/2 to 1/3 of the weeks workouts is nothing to discard. Depending on exactly where you cut, you may have missed out on the most critical workouts of the week. Those are generally the Tues and Thurs workouts, but depending on your particular needs, dropping other workouts could lead to stagnation or drops in fitness too.
It’s not as simple as looking at the time. You have to look at the actual content of the workouts completed (and those skipped). Even with the ones you completed, were they done to their fullest, did you under-perform for any reason, etc?
You have to look at the actual compliance to the workouts and the plan overall. If you are missing or coming up short on workouts, that is a clear issue. It also depends heavily on your prior training history in what has worked for you and what actually leads to progression for your body.