When/How do we learn best?

Is it through hardship, trials and tough times?

Or through success, encouragement and growth of confidence?
This is a question to you. Any thoughts?
My experiment with this (with myself) will continue and I guess I will link back to this a few years from now.
Until then, would love to hear from you.
I posed this question to a couple of ‘wiser’ friends.
One of them replied with –

‘Whenever I am faced with such a dilemma, I ask myself [very deeply] what it would take to replace OR with AND…’