Sometimes advanced students or professionals get caught up in doing a certain number of pirouettes, even when they’re struggling with them. If you can usually do three or four pirouettes but keep falling out of them… don’t keep practicing three or four pirouettes! Dial it back a little and try a double. Or even a single.
Trying to do a nice and controlled double pirouette from start to finish can tell you a lot about your alignment, spot, timing.. everything that is needed to, properly, do multiple pirouettes. Once you’ve figured out what you were doing incorrectly, you will be back to your usual number in no time.