If you get a good tech they should be able to tell you what your ideal signal levels look like, so you can check them yourself when service goes out. Your modem probably also keeps logs so you can see if it's timing out frequently.

Things you can do at home without calling:

Powercycle.

Check coax connections for tightness (not so tight you risk breaking the plastic on the modem).

Unscrew and rescrew coax at both ends.

Inspect the pin inside the coax to see if it's bent or corroded.

If you have a splitter, bypass it.

If you have an extra or known working coax, try swapping it in.

If none of this is working, the problem is either at a splitter inside a junction box (usually outside the house) or at a leg (those big green or grey boxes you see in neighborhoods) or on the pole.

Are you in an apartment? Connection problems can be bad in apartments because the wiring is preexisting and the cable company has to get permission from the owner to replace it. Also, there are often massive rat's nests of cables in huge junction boxes.

Are you in a house? You may be one of the last houses on the line. It technically shouldn't be this way, but often customers in that situation don't get the right signal levels. You may also have bad preexisting wiring.

It could be an outage, but if you need a field tech to come fix it, ask him very clearly where the problem lies and how he knows that's it. If it's a problem at the pole, those can result in repeat service calls as the signal levels never get tweaked just right.

If your problem is bad wiring, see if they'll replace it without charging you. At the last ISP I worked at, a new "home run" line for the modem was included with install, but techs hardly ever installed on. Customers with bad wiring often got a new line installed for free because of this.