"Hi, Would you like to recommend a good eyeliner, have tried some but are never satisfied."
(And after a follow-up question, I found out that she is looking for a liquid that is waterproof)
I always use Kryolan's Cake Eyeliner, however, it is not waterproof but still fits very well all day.
The waterproof that I think is the best of the ones I have tested is IsaDora's waterproof Dip Liner. If I paint it on my hand and rub it, it will not be destroyed at all, but fits just as well. When I put on water and rubbed, it also held, but if I also scratched with my nail with water, it came off quite easily.
In other words, it fits very, very well, but is not bulletproof if you say so :)
Then I can not help but mention Esteé Lauder's eyeliner ”Pure Color Liquid Eyeliner Duo”. I have not tested it myself so I personally can not comment, but Helen Torsgården wrote so well about it in this post that you get really eager to buy it at home. "It keeps in the sun, in the gym, in the rain, in the pool - Everywhere!" she writes in the post.
It can be time to test! :)
Throws in an eyeliner tutorial for fun :)