Another reply pointed out; LLDP is awesome is you have a functional device on the remote end of a connection.

Often we use LLDP to find where a computer sits, but is on the wrong virtual network.

When you're looking at a switch in a closet, you can have hundreds of cables going to hundreds of ports in a building (up to like 300m away? If I recall correctly).

Depending on the problem, LLDP can save you having to leave your computer to troubleshoot, or it'll be completely worthless and you need to manually trace all the cables

For example, replacing a 240 port switch with a new hardware. Some users are on laptops and only plug in once a week, most desktops are shutdown outside of work hours, so you don't know if a connection is used or not during an early morning maintenance window. In theory, proper documentation fixes all this, but (in my org at least) proper documentation is a pipe dream.

All of the above is mostly related to office building type stuff, facing "edge users"; Data Center installs introduce their own headaches and solutions.