Some genuinely good replies on here, thank you.
To sum it all up, would I be correct in thinking you use it to connect to someone to either sell them what you're doing or producing, with a view to either getting them as a customer, or obtaining something that they do that may be useful for you?
Or as a cross referencing CV tool, or a way of advertising your trade.
I've been on it for over five years and it's produced nothing for me because I'm not selling something. I just wanted to know if it's genuinely useful, which it is for some but not for others.
Thanks team!