Sometimes I´m working in a new project and I said, ¨oh damn, I like it, sounds great!¨
and the next day when I open again the project I think ¨this doesn´t work, is cr@p¨¨
(I'm not talking about the mix & master, I'm talking more about the melody, chords and percussion?

Why? I cannot understand, It makes me lose motivation 

I agree with Rixir, music as art is subjective, so you'll never find one true sound that is always good, it depends on your mood and context.

Your topic is something I've thought a lot about lately after making music for 7 years. It's probably the top reason I am pursing other interests lately.  I think it often comes down to a lack of baseline- I'm guessing you don't have  successful musical friends or hundreds of fans you can ask for an opinion.  It's incredibly hard to know if something subjective is good or bad if it only lives inside your head, or on your computer.  Your mood and tastes change day to day and without some form of outside input to curate your creations all you really have is just a diary of your  sonic ambitions.  Most musicians do well to present a certain sound or image, and that usually contradicts having an incoherent collection of random music that you've created.

So your feelings are totally normal, but if you keep feeling like that for years on end with no productive benefit, it's time to try something else. Everyone is good at different things.

Like others have said, don't worry about this man. If you think your music theory and chord/melody writing needs work, maybe take a break from the production grind for a little while to read up on music theory tutorials.

And Rixir is right-- sample selection is really important for percussion. Also think about checking out percussion processing techniques. There's a difference between dropping a sample out of a pack straight into the track and making it fit through processing. (For example, tuning, ducking your bass/synths, multiband saturation, etc.)

your music might not surpass the moment when it was created. therefore it doesn't translate to the future present moment you will eventually  hear the music in.

I suggest you still write music and gain as much knowledge in music and music production.

@Red X:

unless you're obligated for industry-related reasons (deadlines with a label, for example), tbh i wouldnt feel pressured to release it. keep it as a learning tool of what NOT to do, even! can you isolate things in it that you aren't happy with, so that you can avoid them next time? how did you write this song versus something you're prodest of?