Customers just don't know.
Anytime a appliance is not getting water, such as a dishwasher, ice maker or washing machine the customer will often tell me that it's not pumping water into it.
The dishwasher is not pumping water into it. The ice maker is not getting any water, it must need a new water pump.
The one I hear a lot over the years from customers is with refrigerators. Any refrigerator that is not cooling like it should must need freon added.
First, freon is a brand name, so we really have no idea if it even has freon in it.
Second just about anything that goes wrong with a refrigerator will cause it not to cool like it should.
Dryer is taking a long time to dry so they think it needs a new heating element.
If I was not so honest it would be really easy for me to sell parts that customers did not need.