Whilst it can give you an overall impression, I find more often than not that just because something is popular, that doesn't necessarily mean it is any good. Just look at 99%+ of the talentless tone-deaf auto-tuned hacks that make up modern pop music -- or even the history of pop music as a whole. Some real CRAP has made it into the Billboard top 100 of the past 50 years!
Hence how mind-numbingly dumbass bloated broken BS like jQuery and bootcrap have mouth-breathers singing their praises out of ignorance and incompetence.
To that end I use factors like how often it is updated (though that's NOT entirely a deal breaker), how well it is written by actually looking at the code (that is an immediate deal breaker for me), as well as where/how it is hosted. If the project is one for web technologies, and it has its own website, and that website is poorly written bloated crap that screams "I need to learn HTML", I'm not going to trust that they have any business telling me how to do something online.
queue broken record --
As I'm always saying, see garbage like this:
<nav class="navbar navbar-toggleable-md navbar-inverse fixed-top bg-inverse">
<button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarsExampleDefault" aria-controls="navbarsExampleDefault" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<a class="navbar-brand" href="#">Navbar</a>
<div class="collapse navbar-collapse" id="navbarsExampleDefault">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
Where if you don't know what's wrong with that, do the world a favor, back the **** away from the keyboard, and go take up something a bit less detail oriented like Macramé .
If they cannot handle something as simple as HTML, I'm not going to think that anything they wrote anywhere else -- like PHP, JavaScript, Python, Perl, Ruby, whatever -- is going to be worth a damn!
To that end, what other users think ends up pretty damned far down my list! Wizard's First Rule...
-- edit -- ok, why is hashnode screwing with code blocks stripping out linefeeds? Lemme guess, related to the stupid malfing font change?