largely, it depends on your grow space, how much square footage you have and how long you're willing to wait. bigger plants will put out more water which gets trapped in a house, gets on the windows, behind the walls. if this is a concern, don't veg for too long. you also need to grow in soil or hydro properly, without overdoing the ferts. the longer the grow, the greater the chance something will go wrong. cloning and growing them small but frequently might be a good solution like mentioned above.