What *is* a “successful adoption”?

It gets said around – for example, in this {linky} article by (yes, I know, don’t mock, it was the easiest one to find :p) the Daily FMail, that there are such things as “successful adoptions”. (Bolding = my emphasis)

{quote}
And while some adopted children will go on to have behavioural problems because of their poor start in life, there are still many successful adoptions that take place.
{/quote}

So what constitutes a successful adoption then? Is it one where we don’t follow in the footsteps of our “dire backgrounds, where it’s highly likely Dad has been in prison and Mum was addicted to heaven knows what illegal substances and working as a prostitute.” ??

Are we even allowed to want to know our biological predecessors? Or does that make us a bad adoptee?

Does it make any difference if it is our adopters that are abusive, as has happened in so very many cases? Or are we still expected to follow the decree and only recognise our adoptive families (who we generally have absolutely nothing in common with at all, other than shared history) as our “real families”, since after all, they’re the ones who sat up with us sick, and other such normalities?

What makes an adoption “successful”?

I’d really really like to know.

Another point to raise, while we’re on the subject, is …

{quote}
But, unfortunately, the names of these blameless children make their less-than-middle-class backgrounds all too obvious. And most prospective parents don’t want to adopt children who are named after someone’s favourite celebrity or tipple.
{/quote}

… should someone who so obviously cares about such superficial things as the name we’re given by our parents be allowed to adopt in the first place? I mean, surely that exhibits pressures that are going to be applied to the prospective adoptee that should not be placed on a child who hasn’t already experienced such a great loss, let alone one who has to conform in the ways that an adoptee does?