I don't often borrow things because I learned very early on that some people hold it over you even if it's just by tutting and sighing about how much they do for you.
I'm thick skinned but I hate that so I am reasonably independent and well-organised. I'm one of those people who's always got a tissue up their sleeve.
I'd prefer to give things to people (within reason, I'm not made of money) than lend because I'm particular about my favourite stuff and some people ruin things or just keep them. Plus, if it's my favourite stuff that generally means I use it or just enjoy looking at it so I need it.
So I won't lend precious things and I won't lend money that I can't afford to lose but do lend things if I'm not that bothered if I never see again.
That's not to say I have limitless patience. I used to work with someone who was always borrowing things from everyone in the department because she was lazy and disorganised. Because she was so feckless she would often trash or lose them and never replace them.. She once borrowed a piece of work kit from a colleague that everyone who does our job had except for her. It was about £50. She could easily afford one but she always forgot or was waiting for the latest model to come out. She lost it and then whined when he asked her for the money. He never saw the money and bought another one.
This extended to the most trivial things. Because I sat next to her she'd regularly ask me for tampons. Of course, we all have emergencies but this would happen every month. It wasn't because she couldn't afford them it was because she was forgetful and too fucking lazy to buy them when she did remember because it was much easier to ask the girl sitting next to her.
One day I said no and said there was a tampon dispenser in the loo and a chemist with a wider selection next door. She said I was horrible meaning: "You won't do what I want you to do."