Do you make sure all the base functionality is done before you start the testing?
Whoops, should of been in iOS. Sorry. 
I would say when you know what kind of feedback you want and when you are ready for the harsh truth whether people enjoy your game as much as you do.
I mean, we did a pretty early test on bonkadonk and the feedback was coming pretty rarely and the stuff that we got we almost always had to answer with “yeh we know about that”, “yah, this will be changed”.
So we were kinda euphoric that we achieved our first milestone for ourselves but we had so many things that we wanted to add on our own, that it was bound to be dissatisfying for both, our testrs and us. And if people really take their time to givyou honest feedback, you probably don’t to tell them “yes, we know”, it’s disrespectful in a way.
Here’s the pic of our testflight summary:
Thanks for the reply. I think i’ll make sure the game base is complete and then seek feedback from testers, that way (hopefully) feedback wont be on obvious things like pause menus etc.