I halfassed every exercise and did nothing on my plan.

That’s actually fine. Most fitness goals require steady, long term progress, and the nature of a plan with 100+ workouts is that you can afford to have a suboptimal workout, to shift things by a day or two, without setting yourself back on that medium or long term journey.

Terry Crews has talked about how he sometimes has days where he just goes to the sauna, or sits on a bench, and does nothing other than getting his gym clothes on. And it counts. Because on many days where he just intends to go to the locker room, he figures “well I’m here” and does a few exercises. And doing a few exercises is better than no exercise.