If you mean “Is it a serious mistake to never leave the washing-machine door open?”: generally, yes—it can contribute to problems, but it isn’t an emergency or a rule that must always be followed.
Why leaving it open after washing matters
- Prevents mold and mildew: A closed door traps moisture inside the drum, gasket, and detergent drawer. Over time, this can encourage mold and bacterial growth.
- Reduces bad smells: The characteristic “musty washing-machine smell” often comes from moisture remaining trapped after a cycle.
- Helps the rubber door seal dry: Front-loading machines especially have a rubber gasket that can retain water and detergent residue.
- Keeps the machine cleaner: Air circulation helps residual water evaporate rather than remaining stagnant.
What you should do
After finishing a load:
- Remove the clothes promptly.
- Leave the door slightly open so the drum can dry.
- Wipe excess water from the rubber gasket, especially in its folds.
- Leave the detergent drawer slightly open as well, if practical.
- Periodically run the machine’s drum-clean/self-clean cycle according to the manufacturer’s instructions.
Important: You don’t need to leave the door wide open all the time. Once the machine has dried, closing it is fine. If you have small children or pets who could enter the machine, keep safety/child-lock considerations in mind.
So the more accurate statement is: “Keeping a washing-machine door permanently closed immediately after washing can promote mold and odors; leaving it ajar while the machine dries is generally recommended.”