I have been doing this for three years now, and i think my purpose is to improve myself so that i can give out better logo's.
My main idea when i create a logo is to see it as a brand from the begining, and i try this with all my logo's because you need to give your client a symbol that can grow into a brand.
I have gained a lot of experience in my short but well spent time in the world of identity and logo's, went to graphics courses, read everything i could get my hand on (damn books are expensive - but worth it!) also in these three years i have worked with an advertising production company on car graphics, poster and flyer, some web graphics and of course identity.
I hate tacky work done without thought with bad colors and "Arial" (works only rarely) for a font.
I think the main thing a designer should ask him/her self after finishing a logo is: "would i use this?" and if the answer is "no" delete it all and start over :)
you can see more of my work here:
http://mircha69.deviantart.com/gallery/
http://brandstack.com/users/portfolio/logos/mircha69
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