To be healthy teens need to assume responsibility for their lives gradually, as they are emotionally ready for it, but hopefully before they need the skills to live independently. Some of the basic skills they will need include getting up on time, feeding themselves, driving, managing money, cleaning their space, basic work skills, and manners.
I spend a lot of time encouraging parents to be supportive of their teens and hear many stories about how hard it is to stick to being supportive without enabling our teens to be too dependent on us.
For example, if we wake our teen up every day, and one day we wake him or her up late, whose fault is it - theirs for not using an alarm clock, or ours for waking them up late - or maybe for waking them up everyday?
How about screaming bloody murder about the mess in the house - is it their fault for leaving their stuff wherever they drop it, or ours for not teaching (and requiring) them to pick up after themselves every day?
Same goes for coming home after a long day to hungry teens who chose to wait for you rather than feed themselves - who takes the responsibility?
I am not meaning to sound the "it is always the parents fault" siren, really, I am not! I think it is important though to be conscious about how our behavior as parents is impacting our teen. If what we do is comfortable for us and helps them be independent, then great - we are good. If however, we are doing too much for them, it might be worth readjusting everyone's expectations and being clear about or expectations in relation to skills they need to develop!