Thank you all for giving me that much information! It means a lot for my learning about photography.
At the time I took this photo I was thinking just about the snail. I took few photos, from the nearest point possible from snail. I wanted snail to be entirely clear and to be seen eating a leaf. ( No one noticed that, so obviously I did it sooo wrong
) Didn't think about colors, background, snails position ...
Now , after your replies, my sight is a little bit wider. I'm going to post more photos since I believe this is great way to learn from own mistakes. Hope my next photo will contain comments good as these once.