Some friends are good debtors and others aren’t. Part of it is down to money management skills and part is attitude towards paying debts.
Those who are good to lend to don’t need reminders to pay it back - they’ll settle according to their word and as soon as reasonably practicable. These are the friends I won’t watch the pennies with because the give and take is even over the long term.
Those who aren’t, just say no and point them towards family or the bank. If no one else will lend to them, there’s a good reason why.
Lending money isn’t necessarily limited to handouts. Even things like making a booking on behalf of a group of friends - I wouldn’t do it until everyone has paid up first. If you do, you will discover that some friends don’t actually intend to pay you back promptly and view it as an extended interest free loan and others use you as insurance and will simply not pay up at all if they choose to back out - but of course, they will not declare that. The people who protest at having to pay up front, unless they have a good reason and you agree a payback date don’t bother covering them unless you’re happy to be chasing that money from them for weeks or months.
I agree with the notion of gifting rather than lending and would rather do that to be honest. Or if they have a skill that I could use I might give them what they need in exchange for their time with that skill, even if it’s well over the market rate. Just beware of people who are happy to keep taking!
If someone lends me cash or includes me in a group booking, they’re getting their money back as soon as I can get onto internet banking and sort a transfer. It actually hurts my head to owe in these circumstances but some people don’t mind it at all. It’s probably because I’m quite big on living within means and only borrow for convenience.