The solution to that is to properly set expectations. If you're releasing an early preview or MVP as if it's a polished final product then yeah, you'll get bad reviews. If you set expectations of "This is a preview release to get feedback so we can make changes to meet YOUR needs" then you should get feedback. If you've set expectations properly and get bad reviews at that point you should be able to go back to them and note that the review was for an early-stage trial balloon.