As all men know, a full urine-stop mid-flow is a virtual impossibility (achieved only by a select group of Tibetan monks), and there are inherent risks in significant position changing whilst underway; so the terrible series of worries and uncertainties that inevitably follow the sudden gurgle of pipework and the subsequent sound of rushing water cannot be avoided and simply have to be endured.
The biggest fear, of course, are mini-splashes, those annoying spatterings of the crotch area with little droplets which, though individually insignificant, can amount during a a serious urinal self-flush to a large and embarrasing wet patch which suggests a serious bladder control problem. These mini-splashes can have a number of causes:
- flushing water pressure too high
- interaction of the flush-water with an excess of those yellow toilet blocks that smell okay for a day or two but after a week smell only of concentrated piss
- incorrect flush-water entry angle resulting in flush-water not being contained by the urinal design
There is also the subsequent concern about urinal over-flow, when the raging torrent that is the self-flush simply overwhelms the urinal drainage system (because it's blocked by an unsightly mass of discarded cigarette ends, chewing gum and pubic hairs) and ends up gushing all over the floor and splashing up on shoes and trouser bottoms (again suggesting the individual has either bladder control problems or poor aiming capabilities).
It has, of course, long been suspected that urinal self-flushing systems are now being specifically designed to start operating exactly nine seconds after a man has stood in front of the urinal, in just the same way that the urinals themselves are being designed to maximise urine splash-back, all part of a world-wide plot by the manufacturers of black dye to instil in all men an inherent mistrust of any sort of light-coloured trouser material (especially light grey).