Why does Nintendo take that long to make games compared to HD consoles?

[tehsage]

I'm not sure if it's been said yet, but, to my knowledge, most Nintendo games are longer than most HD games. My friend said he beat MGS4, one of the biggest PS3 games, the day he purchased it and it took me awhile to beat Twilight Princess, a launch title.

Many HD developers take a lot of time making the game look good so they sometimes sacrifice gameplay/length.