For junior devs, we don't actually care if they do it in 2 hours, 2 days, or the whole 7 days we allow them. There's no bonus points for turning it in the next day, and I don't think anyone has ever actually done that.
But we're at the point that if they fail a single point in the requirements, we stop looking at them. This was a really hard decision, because there are candidates who are really nice and seem to otherwise do good work, but we've hired some of them and they inevitably continue to skip steps even in simple tickets. We end up letting them go after multiple warnings and months of wasted time, and having to do it all over again.
Of course, if you can't code you aren't going to get in either, but that actually seems to be a lower bar than following directions.
Kids in school often don't read assignments properly either, and skip everything until the first question. I don't know if they think it saves them time or fear there's a trick somewhere that they will avoid that way.
In life in general, people like ambiguity; it helps to smooth things out. But in programming it's a problem.
Nothing complicated - shouldn't take too long.
Why not send people the assignment and ask them to return it within a couple of days? What are you gaining by limiting it to hours and turning it into a remote exam?
I suppose people's preferences vary a lot. Personally, I would turn this down. The format of "do as much work alone under pressure" is extremely offputting. I'd much rather do a whiteboard interview where the problem is well scoped in time and I can discuss my solution with the interviewers. I also wouldn't mind a take-home that actually takes 2 hours that I can do whenever I please - but asking for the work to be returned within hours is a dealbreaker for me.
If you are having time pressure challenges with our assignments we also don't want you.
But also if the person is so unwilling to co-operate that they can't so basic programming skill then I guess it wasn't meant to be.
Let's say there's two candidates for a position who are both asked to complete the take-home assignment, Candidate A and Candidate B.
Candidate A is the superior candidate and spends only two hours on the task (as requested), and Candidate B spends 2 days. Candidate B submits the better assignment and is more likely to land the job as a result, despite Candidate A being the better candidate.