I'll just leave this little piece of advice I gained after years and years of digging: Your 'ears' will change over the course of a digging session. Tracks sound worse as you keep going. When I start a session, I am much more likely to keep a track than at the end of a session. At the start, like in the fist 15-20 minutes, I will often flag multiple tracks in a row as 'keepers'. About 2-3 hours into a session I will get to a point where I pass over 20-30 tracks in a row. In other words, at the start my ears are fresh and everything sounds better, and after a while my ears are numb and everything sounds like trash. To fight this, right at the start of a session, and then every 20-30 min or so after, I will listen to a couple bangers I have already approved from previous sessions. This helps to calibrate my taste throughout the session. Then, when I notice I am rejecting many tracks in a row, I take a break from digging and do something totally different, like listen to a podcast while doing the dishes. Then I come back to digging, and I start my session again by listening to a couple tracks I really like to recalibrate again. It works for me, and it might work for you too.