That's not always the case bro.
If I'm doing bench press drop sets and start off with 350 lbs till just below failure, I wont be able to lift another set of JUST 5% weghts under that if my life depended on it![]()
The idea of the 5% decrease is to allow to maintain the intensity in order to activate the highest treshold motor units, i'm pretty sure that you only be able to get one or maybe two reps at most. Do that over 3 sucessive drop-sets at 5% decrease rest 4 minutes and repeat for 3 or 4 more times. This method works very well for individuals with a large percentage of fast-twitch motor units.