None of us are qualified to state with certainty why certain individuals go to one place or another. Writing off potentially legitimate concerns as insignificant is one reason the problems continue, IMO, though these are difficult to address.
The idea of getting players to fall in love with St. Louis and them taking hometown discounts to stay is a thing of the past. The team knows that too, which is one key reason why they are now trying to acquire players with multiple years remaining (like Ozuna – successful, after Stanton – unsuccessful) rather than rentals – to shore up the roster when farm players are not enough to cover the needs.