I'm just wondering why Wolverine does not appear in his iconic costume when even in last movie there is apparently a deleted scene show such a costume ? See this picture.
Well, mostly because the costume is a bit ridiculous when taken out of the context of four-color comics. Might as well ask why Logan's hair doesn't stick out to both sides as much as it does in the comics: just because something works, visually, in the medium of print comics doesn't mean it will work in the medium of live-action cinema.
As @AnkitSharma mentioned in the comments, the deleted scene is probably a nod to comic fans who have a sentimental attachment to how Wolverine looks in the comic books. But in any adaptations changes must be made, and visual and aesthetic changes most of all, to fit the new medium.