What I do when I REALLY don't want to workout is I go for a PR. Any Personal Record that corresponds with my split, whether on weight or on repetitions. This does two things: One: it makes the workout exciting since l'm trying to do something that’s actually difficult that requires my effort, not just meandering through the motions because I know I have to. Two: it's very psychologically empowering because I didn't even want to work out at all, and I managed to hit a PR on a day that I didn't even want to be here in the first place.

I almost never have a set that ends in 10 reps. We’re going for genuine muscle failure here—it’s much less likely that we happened to hit muscle failure at exactly 10 reps than it is that we stopped at 10 reps because that was the preset number that we had in our minds before we started. We can convince ourselves that we hit muscle failure, but we usually had a few more reps in us that we would’ve hit if we weren’t so content with stopping at a round number.