Tanks may crack and the screws may rust. Look for a faulty washer between the tank and the bowl if there is water leaking around the toilet.
The closing connections of the power supply line and toilet must be dry. If not, check for loose supply line or rusty shut-off valve.
Check for water around the edge of the toilet with the floor. Often, the flange is too low so it does not make a proper seal with the wax seal, and when installing the toilet, two joints should be used. If, over the years, the toilet is replaced, in particular by a homeowner, “they install it using a single wax seal, as they do not know, and the water escapes because there is space around it.
On the other hand, sometimes installers do not follow the instructions to put the wax seal on the floor and then install the toilet. They will put the gasket on the toilet and after they put it on, the gasket will fall off or out of position and the bath will drip.
The correct thing is that after installing a toilet, try it before installing the seal around the toilet rate. If water escapes through the wax seal you can see the water coming out. Otherwise, it may take a long time before the leak is noticed.