OK I'll bite
I've almost been on this site for 10 years! In December it will have been 10. The only reason I started using my account was because my friend AmandaTurnage (https://www.deviantart.com/amandaturnage) started using hers, and I wanted to be cool too, although I'd browsed here before that. The word "deviant" kinda turned me off initially (thought process "hey no I'm not deviant"), but now the word has lost nearly all of its original meaning, haha.
Without deviantArt I'm not sure I'd be where I am today, with just enough internet-cred to make friends with all the cool artists and get enough money out of my hand and to continue to put food in my mouth... but I've gone from