Why does Deidara hate Tobi?

well, HATE is a strong Word but perhaps nearly close enough for Deidara's view on Tobi.
Deidara dislikes Tobi as he believes all Akatsuki members should act serious and calm not relaxed and goofy.
I think personally, Deidara was just disappointed when he lost his first partner Sasori and had to work with Tobi.

BUT Deidara does show minor respect for Tobi, as seen before his death, he apologizes to him~