Listen to the file, not the session
A delivered file that matches the mix you approved, checked end to end, with peaks that suit where it goes.
The problem
The session sounds right, but the listener only ever hears the file. A missing tail, a wrong version or a clipped transition can hide in an export until someone else plays it.
What to do
Before you export, check what the destination asks for: the sample rate, the bit depth, the file type, and whether it wants stereo or mono. A preset from the last job may not fit this one.
If you're finishing the master yourself, set the limiter for where the file is going. On Finish Him, set Ceiling for the destination before you bring up Drive. A streaming upload, a CD master and a file for a video editor don't all want the same headroom.
Export, then open the file somewhere outside the session, such as a plain media player. Listen to the first second and the last few seconds, where count-ins, fades and tails go wrong. Then play it through once, start to finish, without stopping to fix things. Note the problems and fix them in the session afterwards.
Measure the exported file, not the session meter. Encoding to a compressed format moves the peaks, so check the encoded version as well if that's what you're delivering.
When to stop
One full listen is enough if nothing is wrong. If you find a problem, fix it in the session and export again. I give every new export a new name, so nobody plays an old one by mistake. If the file is going to a mastering engineer, leave your limiter off and say so in your note.
The test
Play the file on a different system from the one you mixed on, such as headphones or a phone. It should sound like the mix you approved, start where it should and end with its full tail. If you can tell which version it is from the file name alone, it's ready to send.
Rory