Let me put it this way, I left A-levels because I felt I wasn't learning anything. The subjects were Media Studies, ICT and Geography.
I didn't have a clue what Media studies was all about but I was told that part of it was related to computers (meaning I only enjoyed the computer side of it).
I wanted to take the Geography route because I had an interest in Physical geography but my main weakness was settling into a group in a field trip gathering data.
And ICT wasn't even what I was looking for, I really disliked the business side of it and so it gave me a bad grade but the only grade I achieved (the other subjects were both unclassified).
You see, I only got out of A-levels because: 1. The above reasons. 2. The school I was at limits me to the subjects I can study according to my GCSE grades. 3. It takes me an odd year to get all the information to sink in which I need for examinations.
I'm not against BTEC and it has taught me alot over the years that I wouldn't have done in my chosen A-level subjects - if I was at another school I would have taken more academic than vocational. It's important you choose what you really enjoy, and if things don't work out follow your interests/hobbies like for me it was computers so I chose BTEC in IT.