The match score shows how well a candidate fits the criteria of your search. NIXZ looks at the content of the profile and at the traits that matter for that specific search.
How to read the score
The score is a prioritization aid. A higher score usually means the candidate fits the current search better.
The exact result depends on the number of criteria you set and how many of them are a full or partial match, but also on the quality of the profile and the information available in the source.
Practical use
Use the score together with the evaluation and the profile. That way you see not only who scores well, but also why the candidate may be interesting.