He may be trying to let you know something is wrong. He may have a urinary infection (or crystals in his urethra) and is having trouble "going", so he lets go when and wherever he can finally manage to squeeze some out. This is a VERY common problem, for male cats. And that's a very common behavior when it happens (or if he pees elsewhere in the house, suddenly). -- Get him checked by the vet. If he gets to the point where he can't urinate at all, and his urine backs up, his kidneys can shut down and kill him (which can happen in as little as a couple days). If the vets determines that's the problem, antibiotics and (maybe) a diet change will fix it.