I think every season. You should get 3 more refunds. Because it would be better

Don't worry i took the liberty of editing it for you.

That isn't even that great of a reason ._.
Riot does need to make money, I honestly don't want to refund anyone at the moment and I used all mine.
Don't buy something you would want to refund later on.

They gave 3 refunds, be glad they gave those, its your choice of when to use them. If you've wasted yours, it is your own fault, not Riot's. Sorry if i appear to be rude, but its a simple point.

I think this makes sense though, very often people buy a champ after their free-week and later get nerfed or changed, making you never play that champ again and after you have already used your refunds for mistakes and regrets.

It doesn't make sense for Riot to continuously replenish refunds because champs get nerfed or changed. Anyone who plays an online game should expect nerfs and changes as the game matures. I get having refunds available for buyer's remorse, that's why I refunded Kha'zix and Syndra but that's why you have to be more careful with your RP. Personally, I spent most of my RP on skins since you can just as easily buy champions with IP which is free to you.