It can be really challenging to know how much tension to apply when we'd like our kids to do stuff, because we believe it'll be good for them. If you get resistance, consider the following before deciding how much pressure to apply.
Check your own motivations first. It's wonderful when they experience a sense of achievement that comes from seeing effort pay-off, but are we 'pushing' them for selfish reasons?
Get an idea of whether their temperament / interests / stage of development matches the nature of the activity. Knowledge of your child and student is key to understanding how much 'pushing' they can tolerate.
Ask if they have the skills to cope with the demands of the activity. Do they need help upskilling in a specific area so it increases their chances of enjoying it?
When you think it's time to push; apply gentle pressure, like when you're teaching them how to ride a bike.