Words of wisdom? Yikes!
Patience, I guess. Often the ones who are slow at the start catch up later on. A big barrier is if they feel they are being expected to do something they are not sure they understand, (lack of self confidence) and are worried about making a fool of themselves in front of their esteemed instructor.
Reminding them that you are always on their side, and a few anecdotes from your own student days when perhaps you weren't quite as perfect as you are now can help
! You can of course say "A friend of mine, when they were learning to fly...etc etc"
And reminding them that you can learn more from stuffing it up first then getting it right, than you do if you get it right first time!
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