Dishes are not clean at the end of the wash cycle?

The Dishwasher is overloaded. Reduce the Dishwasher load. Ensure the spray arms can rotate freely and remove food scraps from dishes before loading.
The spray arm holes are blocked. Remove the spray arms, rinse under tap water and replace.
Not enough detergent has been used. Use the recommended amount of detergent.
The strainer is blocked. Clean the strainer.