Because we use the word very a ton in casual conversation, it tends to surface in our writing a lot, too.
Does the fact that it's colloquial make it wrong? Nope.
It can be used to add emphasis, and it can also create strong rhythm, like in the sentence Cinnabon's cinnamon rolls are very rich, very gooey, and very tasty!
But it's easy to slip into misuse and abuse of the word very.
Common Abuses of Very
(1) Overuse. Go easy on it.
(2) Try not to use very when you could use a more original adjective instead. Let your creativity flag fly.
(3) Don't use it to intensify an absolute like unique or dead with it. There are no degrees of being dead—someone or something's either dead or it isn't—so don't modify it with very.
(4) Don't confuse very with its cousin vary. Vary is a totally different word that means to differ or change.