(as) regular as clockwork British simile
Something occurs very often and can be easy to predict.
The buses at my place are always regular as clockwork.
As regular as clockwork, she leaves the house and walks to the office at 6 every morning.
Something that happens on a daily basis
Used to say that the telephone is ringing constantly or very frequently.
The phrase came into use in the mid-1700s. The word "clockwork" refers to the inner workings of the mechanism of mechanical clocks and other similar mechanical machines.