I've been watching old series of the show, and I forgot that in the early days there was a job on offer!
I know functionally it makes no real difference when watching the show , but it can still affect things. Like, if someone in the boardroom has a business which Lord Sugar has no interest in, he probably wouldn't keep them over someone with a techy business.
On the other hand, tasks can be made especially to test the candidates' acumen in their chosen area, like last year the dude who wanted to make an icecream company flopped hard on an icecream task
So of course he'd be fired, no brainer.