Reasons for delay in adoption order after placement

[TulipsfromAmsterdam]

After reading a few posts on here where families have waited a long time between placement and the adoption order I was wondering what kind of reasons cause the delay.
I ask as we have recently been approved and matched with our beautiful fc and hope it will be straightforward once we apply to the court but would like to be prepared for any delays and the reasons they occur.

In our case, dd's social worker left and nobody seemed to pick up her caseload. So we were told six months, but it took double that.

we have waited because DD was older and we wanted to see if any issues arose. Getting her help after adoption would be a PITA

Because DD1 was older, the SWs waited 9 months before they gave us the go ahead to adopt.
It then took 8 months to get to court. Oh how we wished we hadn't told DD1 we had had the go-ahead to apply....
In our case the delay was because the birth family decided to contest the contact arrangements.

With us, firstly they recommended we wait until a review that I think was at about 4 months after he came home.
Then life got in the way a little bit.
Then we were getting no joy getting his life story work from his (rather slack) social worker, so we decided that we would only do adoption order after receipt of the life story work and made sure she knew that.
Then, there was some reason why we couldn't put the papers in the court. There was a piece of paper missing and it was one that we had never heard of or received.
Then his social worker gave us the wrong address for BM so when it finally got to court, someone realised the address we had put on the forms and the address that slack social worker had given us were different. They use the one that we put on our forms to send notification to BM so obviously she wouldn't have received it, so it was delayed by (I think) another 6 weeks until another court date was available.

So adoption order came through 11 months after placement.

Someone I know had a child placed with them, but then a birth parent decided to raise a court case to contest the adoption.

After the case was dealt with the adoption went through, but took months longer than it could have.

Social Workers workers were excellent in this instance I have to say.

Thank you for all the replies. It seems it isn't always as straightforward as you expect/hope but it is good to know what to look out for. I think I expected most hold ups being due to bf contesting the adoption. Thanks again.