Why can't I ollie on the spot?

Question

I have probably the highest ollie of all my friends and can ollie on to basically any block at skateparks even up a 2 stair but when I'm playing skate or someone asks me to do a trick I can't. Why??

Answer 1

probably cause theyre putting you on the spot and then you dont have time to get ready

Answer 2

Keep in mind that this is only flat ollies. If in skate i have to ollie up something I can do it.