I am not talking about watering them, it's about actually training the bonsai you have.
- I check all of them for watering needs twice a day.
- I pinch, prune, wire, unwire, tweeze them for weeds, pluck old needles, check for pests, apply peroxide, fungicide, neem oil, and rotate them every two days in average.
I am lucky, having a bench at work and some tropicals at home, so I can work on them whenever I get free time.
Some of my big trees are in the countryside, at my brother's property, so those only on weekends...
What about you?

Clicio wrote:

- I pinch, prune, wire, unwire, tweeze them for weeds, pluck old needles, check for pests, apply...

If they need, of course!
If they don't, I live them alone.

Typically every day!

Twice per day. In the morning mostly watering and looking for pests or health issues. In the evening is when I study them and do some tweaking. All of mine are growing trunks and roots so I am mostly trying to keep them healthy until they get bigger.

Depends on the season, the weather, ... but i try to at least check ( or water, ...) everyone of them once a day