If you asked five staff members at your library to weed the same shelf, you'd probably get five different shelves left over. That's not a staff problem. That's a policy problem.
Most small libraries have a weeding policy that says something like "remove items that are outdated, damaged, or no longer circulating." Technically true. Completely useless.
Here's the fix, adapted from the CREW method, but trimmed down for a library with no extra staff and no extra time:
Give every section two numbers, not a feeling.
- A circulation threshold: for example, "fiction with 0 checkouts in 24 months gets flagged"
- A condition threshold: for example, "anything with water damage, broken spines, or missing pages gets flagged regardless of circulation"
That's it. Two rules, applied consistently, beat ten thoughtful paragraphs that nobody can apply the same way twice.
One thing to avoid: don't weed reference, local history, or anything with archival value using circulation numbers at all.
If you want a full framework, including how to handle the "but a patron will complain" conversation with your board, that's covered in Collection Development on a Constrained Budget.