But you're not actually applying the scientific method here - you're giving in to an emotional response, the exact opposite, because you've decided that errors in production are somehow negative. I keep telling you that they're not - that they're a key part of the process - and that working through the sessions and making the errors is exactly the road that will lead to memory formation and speaking ability.
In fact, if you were going through the sessions and not making errors, it would show that you were wasting your time by dealing with material that didn't need to be revisited at that point.
What you're currently doing is exactly what language learning looks like (at its most effective). So regardless of the natural ebb and flow of how many errors you make in any given session, every time you complete a session you have, in fact, done well - because you've taken the next step on the road to conversational fluency.