Pain in the arse

It is a right pain in the arse when you go swimming, and the place is packed with people. You decide to swim in an empty lane which has a "swimming lessons" sign at one end, because nobody is using the lane and it seems that it is a waste of good water space. Then, as more and more people come in to the pool, they change the lane sign to "fast lane" and "slow lane". My lane gets taken over by fast swimmers, so I move in to the slow lane. Then, as more and more swimmers enter the pool, the "slow lane" gets dominated by the slower fast swimmers. I leave.......fed up.