I sell 5-24 hour long online courses. A two week trial would let someone see everything, and would leave the user with no reason to purchase.
This is why I haven't done full free trial yet. Because 2-3 days seems short. But I'm wondering if it counterintuively might be optimal, by removing friction to trying the course.
I.e. a 6 month refund window may have a lower overall refund rate than a 1 month window.
It gives users who are on the fence about the value of a product more time to see how they've gotten value out of it. It also gives people longer to forget to ask for the refund.
The only reason some companies have a "1 year" refund policy instead of "lifetime/anytime" is because of issues like credit card merchant processors being uncomfortable with the credit risk that creates.
It's just downright ridiculous/shady.
Ridiculous since there's no way I'll be able to make an informed decision in 2-3 days, especially since there's no chance I'll dedicate 100% of my time to those 2-3 days. When I'm done looking at the several options available, I'll have a meeting showing my findings and running through a guess which software isn't going to have a live demo.
Shady, because I know I'm not going to get a full picture in 2-3 days, but more importantly, they know I'm not going to get a full picture in 2-3 days. My assumption will always be (and is usually correct) that on the surface things are fine, but if you try to use any of the more advanced features/integration/whatever actual use, you'll run into trouble.
If you actually have a good product, why fear letting people see how good it is? Let them try it out, integrate it into their workflows enough and see enough of an improvement that they don't want to go back.