Take your project, whatever it is, on a laptop. go to the nearest pub or bar, not the drunken kind but the calm almost Starbuck like.
Find someone in the range of who your average user is, and offer to pay them a beer if they agree to use your interface to do some simple task on it for five minute while you take notes and record the screen. It's a sort-of game for them, short enough that it won't be a hassle, and they get a free beer out of it 'it's inexpensive for you and will reveal some obvious issues faster than a team of dedicated qa tester can ever hope to be.
Here it would be a simple "here is the alarm you get, identify what is the problem and where it is". Given parent post, 5$ and ten minute of beer testing would have told them how terrible it is.
Works fine with group too, ensure one person is the dedicated user, and offer to pay their drink tab.
Be ready to engage with them if they have question and do not be timid about keeping their drink coming if they so desire, as long as they provide valuable input.
It's so obviously stupidly simple, but the result are insane, it's very cheap and you get a perfect case of "how will average person x understand and deal with my software in that situation".
(first learned of it on a hn post years ago, adopted it for fun, kept it because it works too well)
Basically how the Persians used to debate:
"In Herodutus’ discussion of the Persians, he wrote (Book I, chapter 133) that they decide upon important issues by first getting drunk. Once drunk, they start the debate and then come up with a decision. The next day when they are all sober, they decide whether they want to go through with the decision made. If yes, they go through with it. If they decide against it, they drop it and go back to square one which starts by getting drunk again."
