The only thing that guarantees progress is progression. Pretty obvious, right? So why are you focusing on anything but progression? Feeling the burn. Getting a huge pump. Driving yourself into the ground. Crippling soreness. Not being able to drive after leg day.
That all sounds cool and most are considered badges of honor, but none of that guarantees that your workout was effective and will lead to improvements. Yet we prefer to focus on these elements rather than on objective progression. Here's a training method to keep you focused on what really matters.
In the double progression model your goal is to complete a certain number of sets for a certain number of reps with the same weight, like 5 x 8 with 200 pounds.
Use a rep range where there's a difference of about 3 reps between the low end and the high end. For example, 5-8 reps. Your goal is to complete all your work sets in the upper end of the rep range. If you select the 5-8 rep range, the upper end is 8 reps.
When you're able to complete all your planned work sets with the same weight at the upper end of your selected rep range, you can increase the weight at your next workout.
If you fail to reach the upper end on some of your sets, for example if you get 8, 8, 8, 7, and 6 reps for your five work sets, that's fine, but it means that at your next workout you have to use the same weight. You don't get to add weight until you can complete ALL your sets with the upper end of the range.
That's real progression. And that's what you really need to build muscle and strength.