Probably the most common “wrong fit” for students leaving college (either transfer or dropping out completely) is the financial fit (i.e. not being able to afford to continue). See page 7 of https://www.publicagenda.org/files/theirwholelivesaheadofthem.pdf .
But also, academic struggles may matter. 4.0 HS GPA students are less likely to have academic difficulty in college than 2.5 HS GPA students, for example.
So it is no surprise that colleges with high percentages of students from wealthy families, good financial aid for the rest, and highly selective admissions have the highest retention and graduation rates.