From the good folks at Reedsy:
Dynamic Character: How to write a compelling protagonist
A common criticism of fiction — be it in film, television, or novels — is often laid against characters seen as “flat” or “two-dimensional.” Modern audiences know when a protagonist or supporting character isn’t interesting, based on their own lack of emotional investment in that character’s journey. Rightfully fearing this criticism, a lot of new authors are compelled to ensure that their protagonist is a dynamic character. However, as many editors will attest (and as some authors will admit), there is often confusion between “well-written characters” and “dynamic characters” — which are not always one and the same.
Learn more here.