fuel tank water drains
on old aircraft Boeing 707 lots of water could be drained out.
On modern a/c there are jet pumps with inlet pipes at the lowest point in the tank to suck the water up and put it at the inlet to the main booster fuel pumps and gets sent to engine. So there is not a little stagnant point where water collects any more to drain out. If aircraft is on the ground for a long time and the fuel settles the water will collect at the water drain point, so at a transit airport when the a/c lands and is refueled and departs with in 60 minutes it is a waste of time checking for water.
Seen a 45 gallon drum filled with water drains at African airports so the checks is still done at certain transit stops.