If you want to avoid wasting entire evenings on profiles that do not fit, you need to learn a few simple signals before the first match even starts. That is often where long-term quality is decided.
A good gaming teammate can often be identified before the first match. The strongest signals are the clarity of the first exchange, the consistency between what the person says and wants, their real schedule, their voice-chat habits, and how easily they propose replaying if the fit is good.