3 years out of undergraduate school?
The program I dropped out from was, as you say, 3 years on paper. However, you had to have already a masters degree in roughly the same area of expertise as your dissertation theme.
Otherwise, they had a "special" Direct PhD program where they would put you in the same classes with all the introductory classes with the rest of the masters students (4yrs vs 2 + 3 yrs).
Besides that, everybody knows that figures are extremely optimistic. I have heard from different people that 4 years is considered the bare minimum you need to finish. Then, there comes the limbo of post-doc stints before making it to adjunct professor.
PhD is a long and uncertain education path... that leads to an even longer and more uncertain career path.
Oh, and you will be 5+ years older that everybody else.