Dishwasher Not draining at the end of the cycle
First step always, check the filter of the dishwasher. If once cleaned the problem hasn't been solved, check the drain hose, if still is not draining. In some models, not all of them, check the drain valve (if it's frozen, then the solenoid valve should be replaced).

The first step is the easiest and fastest one, the last one is not so easy (and includes some electrical knowledge). Believe me, people usually don't know how many times problems are solved (dishwasher, washing machines, water purifiers...) only cleaning filters.