I see a lot of Excel questions, but also ones involving command lines, batch files, and other similar scripts, that entail some mental challenge.  I'm not referring to ones where a novice needs some basics and the solution is straightforward.  

Users will post what looks like a good answer, reflecting a significant time investment to figure out the solution and write it up.  Often, the solution is obtuse, or long and complex, not something you can glance at and recognize that it will obviously work.  

But the author doesn't go the last mile to include a demonstration of the results, like a screenshot of the output.  I can't tell if it's correct without investing the time to recreate the spreadsheet, and I don't want to upvote the answer if I don't know that it actually works.

If I happen to catch it later, and the OP has accepted it or commented that it worked, I can take that as evidence and upvote it.  But at least for me, a lot of contributors are leaving easy upvotes on the table by not finishing the answer.  

I suppose I could leave a comment.  But then I would look like the only dummy for whom the result wasn't obvious.  And the author may have discarded their work by the time I comment, so going back to reconstruct it may seem like too much effort at that point.

My guess is that the author is focused on satisfying the OP, and expects that the OP will be doing the verification.  But that misses the community at large.  Good answers should address the audience beyond the OP.

Do people besides me not upvote answers that they can't easily verify?  Is there something we can do to educate and encourage authors to include the results as proof on non-obvious or non-trivial answers?