Most people don't have a separate ice maker in their house. By far the most common is an ice maker in the freezer compartment of your refrigerator.
Ice makers are very simple appliances but they cause more than their share of problems. Even though many are modular now, you can often buy the ice maker parts you need rather than replace the whole unit.
Ice makers break down for some obvious reasons. One, they operate in a very cold environment - usually 0-5 degrees. Two, they have several moving parts made of plastic. Three, when the water freezes a mechanism has to push the cubes out of the tray and into the ice bin. All of this means the ice maker is doing more work in a harsher environment than most appliances.
The key to a long life for your ice maker is with the parts you use, and the water you supply to the appliance. If your refrigerator has a built-in water filter you will generally have fewer problems with the ice maker. This is because the filter removes the kinds of impurities that can calcify inside the ice maker cube tray and cause the cubes to stick. When the cubes stick, it's a lot harder for the ice maker to push them out.
It's also important to use the right ice maker parts. If you need to replace the water inlet valve to the ice maker, be sure to use genuine ice maker parts, don't use generic. The genuine parts have been designed to fit your ice maker perfectly.
It's also important to clean the bin where the cubes are stored. Over time the bin may absorb refrigerator odors to the point that all of your ice cubes start smelling and tasting bad. By replacing the bin with the proper ice maker part you will once again have fresh smelling and tasting cubes.
Finally, if you end up needing to replace your ice maker, nothing could be easier. Most ice makers are held in place by two to three screws and have one power cord which plugs into the refrigerator wall nearby. For an expert, replacing an ice maker can take about 2 or 3 minutes. For an amateur, perhaps 10 to 15.