What constitutes an unfit parent?

Abusiveness, neglect,
It depends on what is going on and to what extent, the circumstances, etc...
Like if a 10 yr old is being left alone at home so the mother can work is different than leaving an 8 yr old home so they can go to the bar.

In America, an unfit parent is anyone who does thing differently than you would and you're willing to make a big deal about it. An unfit parent is someone who isn't as smart or as nice or as financially capable or as generous or has as good a life as you do.

In America, an unfit parent is an attitude people seem to think can be thrown around without realizing just how dangerous and cruel it may be.

Meanwhile, there are unfit parents. If you suspect one, briefly tell us why, but before you do, make sure none of the stuff I wrote above applies to you. If it does, maybe you should drop it. If not, share with us more about your real concerns.

In my opinion an unfit parent is... abusive,uncaring,leaves a child alone without supervision, doesn't care for the child on a daily basis... clean clothes,food,love them, comfort them in their times of need,listen to their worries, protect them at all costs, show them the right way in life.
There are many things that come under this heading,but basically someone who has no feeling for their child allowing it to do what ever it wants,as long as it's not under their feet.

My opinion only