Not to sound harsh but this is business (a great one! but business never the less) so you should act accordingly.
It's completely ok to try to move them into action after registrations but if you see that nothing happened, that they don't want to work and were merely curious about this job, you should just let them go. Don't waste your energy on them. You could use that valuable time more productively.
Just work with the workers, like Gery says and you can't go wrong.
Hope this helped.
xoxo
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