However, the question did strike me as something that a player who does this might ask themselves. We might think of the way this could be bad in two different ways: bad towards the self, and bad towards the group.
Bad Towards the Self:
Variety and experimentation allow us to discover more about ourselves as well as lead us to new passions. Playing the same character type over and over might allow us to act out a strong wish fulfillment we possess, but it does not lead to growth.
However if you already know yourself well, you know you hate playing a warrior or detective, but love playing the amoral mage, then by all means play that mage.
Bad Towards the Group:
This complaint was also listed in the post on wish fulfillment, but if you play a character that doesn't fit into the particular game you're playing: You want to play the asskicker in a game of subtle investigation, then both GM and the other players might easily grow sick of your character. Constantly insisting on playing the same character type, especially in stories that really don't support that character, can become annoying and might alienate you from a group of gamers unless they plan on playing a game that would fit in with the character you always want to play.
However if you're willing to make small changes to that basic character you find yourself playing you might find the group appreciates what you bring: You like playing an asskicker. BUT in a game of investigators it might help playing a highly perceptive asskicker. That way you contribute to the group's larger goal, but still have a talent that others in the group may not possess.
Role play games offer us the chance to explore ourselves or pretend to be people we're not. You might enjoy constantly trying something new or playing the same character type frequently. In either case it's good to be aware of the benefits and drawbacks of how this can affect the game and group.