The question is not really "how to know your startup is failing right now." I think it's pretty obvious when a startup is already failing.
The question is, instead, what the signs are that a startup is on the "wrong track" and will inevitably begin failing six months to a year down the line.
I've worked at several companies that were already in the "inevitably going to fail" category before I was even hired—retroactively, looking at when they took on the qualities that ended up killing them, they had those qualities for my entire tenure there (though they didn't previously had them; frequently I was hired as the replacement for the key cofounder whose departure, according to others there, signalled the beginning of the end.)
So, I don't want to know whether my startup is failing. I want to know whether a potential employer is failing, so I can avoid riding yet another startup into the ground and suffering through the inevitable cash-crunch and lay-offs. What are the warning signs, visible from the outside, that a startup is headed that way?
I can't say this inspires very much confidence. Why does hiring MBAs mean you are successful? What exactly do they do to make you successful? On developers, if they have the knowledge for the job then they are qualified, not less qualified. This terminology is very worrisome. And motivational posters? That was a joke I guess?
And what does any of this have to do with being on the brink of failure or not? You can have a perfect team and still fail because of a bad product direction or market fit.
Therefore making them perfectly qualified for the job you are giving them?
There is nothing wrong at all with less experienced devs working for a startup. It is one of the components for building a successful company. As your junior employees grow, they move into roles of greater responsibility.
Some of the other signals could just as easily reflect management's reading habits. It doesn't mean the other comments are wrong, but if you are looking for "early signals," be honest with yourself and hone your trust-dar.
I would flip the question back to you: (1) Do you trust your CEO? (2) If you DO trust the CEO, then the only time your startup is failing is when the CEO tells you they're close to failure, running out of money.
If you DON'T trust your CEO, then your startup is also failing and #2 doesn't apply.
That's how I would think about it.
I think every startup employee has the right to ask me about runway, cash on hand, etc. I would be open with that info and have shared these metrics in the past with them.
I say this because we (a) hire MBAs, (b) hire less qualified developers for roles that do not require deep technical knowledge, (c) have motivational posters, etc... And as we grow, become profitable, and scale to 50+ people, we require these things simply to survive and thrive.
How could someone mistake that for a startup on the brink of failure is beyond me, but that's what some people seem to be writing in these comments.