Listen to the whole track before ever DJing it. That may seem self-evident, but given the time pressures of modern living, and the urgency need we can feel to build up a great collection of music as quickly as possible, it’s easy to get half-way through a track, go: “This is a great version! Next!” and add it for later DJing.
Which, I suspect, is why I’ve seen dance floors cleared by distinctly non-dancer-friendly drum solos in otherwise amazing tracks (here’s a classic from the end of Bob Crosby’s amazing Smokey Mary, where Ray Bauduc seemed to get a little bit carried away)
Probably the most common issue is when there’s a lot of rapturous applause at the end – a little is fine, but too much, and it needs fading off.
Nothing I’ve heard quite beats this one though, which comes from a live recording of Duke Ellington’s Fickle Fling, presumably from a radio broadcast. Admittedly, it’d be hilarious to hear this happen out on the dance-floor, but I’m not sure I’d want to be sitting behind the DJ desk at the time.
So … yeah. It may take a bit more time, but it’s worth it, especially as a little judicious editing can make the difference between a track you can’t play, and an absolute killer.
On the other hand if you are DJing for an event for your local vintage society, that radio interruption in Fickle Fling would be great 😉