It's hard to characterize in a single sentence, so I'll just break it down into its constituent parts.
The Beep
When the laundry cycle finishes it does the following:
- It beeps super loudly for 5 seconds
- If you don't run to switch it off, it will wait 30 more seconds and then continue to beep super loudly for 5 seconds
- If you switch it off whilst it's beeping, it will continue to finish its beeping
- There is no volume setting nor any way to switch this off.
The Door
When it's finished. It does not release. That beeping sound from earlier to tell you to come get your laundry? No no no, that was just the "come and watch me drain" alarm.
- Switching it off has no effect on the door release.
- It releases whenever it wants. It could be 5 minutes, it could be 20.
- When it does release, all you will get is a sound, so you better be around to hear it.
- If you miss this sound, it will lock itself again 10-15 minutes later and rotate your clothes.
- It will then repeat the release process.
HELP ME. HE-ELP ME.
Ironically, the cheapest machines are less likely to be annoying in the way OP describes because they have less fancy electronics (or might even still be electromechanical if it's an old design, but probably not because PCBs and microcontrollers are even cheaper nowadays).
Even expensive machines aren't necessarily higher-quality these days, unless you're really careful to do your research and buy the right brand. For example, I would not actually expect an expensive Maytag to last longer than a cheap Amana because both brands are owned by Whirlpool and might very well share a bunch of the same internal parts. The Maytag would be fancier and prettier, but probably not actually better-made.
Having just replaced a Maytag appliance only 4 years into its supposed 10 year warranty (that only covers the parts not likely to fail) because it would have cost as much as the machine did new to fix it, yeah... The Maytag is absolutely not better made and their "reputation" is just false advertising