Picard is notoriously bad at matching 1-track singles since they are not clustered and therefore treated as recordings instead of releases when doing a lookup.

Often files will be matched to the wrong recording/release by a different artist with a similar title or just the wrong release (album as opposed to single or vice versa).

Manually finding the correct release is just as bad a experience since the results in "similar items" aren't much better most of the time. The only recourse seems to use "lookup in browser" (/taglookup) which often has surprisingly good results with the expected release at the top.

However the "lookup in browser" method cannot be used for multiple selected files (or any item in Picard for that matter), so it's very laborious.