Cylinder #7 down on compression

Many times we have an interference engine (when the timing belt breaks/jumps and bends a valve) vehicle come in on a hook, it can't be run or cranked till the belts back on, and only after the bent valves are repaired requiring the head come off before any test can be done .
When the head is pulled, it can reveal many things that may cause you to wonder about the engines general condition.
Sooo, Let's say it's a four cylinder, if you put all pistons equal distance down and add fluid to brim, and 1 cylinder drains in 20 mins, the rest hold some fluid overnight.
What conclusion would you geniuses draw from that ?

On many occasions, many, - that leaky piston would have a broken/stuck ring.

I just have more/different experiences than you, working on dozens of daily drivers a day, for a very long time .
Having an open mind helps too .

Happy turkey day !