Why do all the cherries fall off my tree?

I have a cherry tree near my garden - every year the same thing happens - lots of blossom and then fruit drop - most fruit trees do it to some degree they lose the excess that they cant cope with - is your tree very dry? It should only lose a few cherries not all of them - when I ask if its dry you need to give it a good soak and then some more! At this time of the year it needs loads.

Thanks for the reply Genuisscufffy. It does get a regular water but perhaps it's not enough!