I would start with the pertinent question raised above:
Define a poor page!
This can be measured in a few ways - the obvious being
links and
traffic. But that could lead to mistakes, since there is also
potential value in those pages - perhaps if you amended them or otherwise improved their standing (e.g. by making them more prominent).
Of course, the main consideration is what you want to get from the fact of having a page. In many cases this is likely to involve some sort of eventual interaction - be that a sale or even a like, or just knowing that someone has found the content useful or as a historical record. But fundamentally, if a page has no possibility of providing value (however you personally define that value) then why would you keep it?
It's not any different from a store dropping products or ranges because they don't (and can't) serve the purpose intended for them. If you can happily draw that conclusion, drop the pages as they are a waste of resources.
My other comment would be that there is both a cost of creation
and a cost of removal (albeit likely to be small cost in many cases). Unless you're talking about removal on a large scale, the net gain is not likely to be very high, so you might end up with an exercise of tidying up for tidying's sake.