Of course there are valid excuses, but like Mark said, to have 5 rides closed? Quite simply not good enough... Samurai was closed prior to Fright Nights to get it ready, Slammer is Slammer, the water rides seem to be closed because of poor organisational structure in the maintenance... No-one seems to know what's wrong with Saw...
Though, there shouldn't be excuses, valid reasoning instead is a lot better... But given that the park has several months shut over Christmas, there's clearly something wrong internally with the maintenance, as there has been for many, many years now...