Maya 2011Unfolding Uv Mapps Part 1

[Lichachron]

hi , wanted to ask something if u could help me:

at 1:47 when u drag & select the faces at the right arm with the lasso tool..

when i do that ,it leaves the back faces unselected ,so i go to persp view again and select them manually..

but even when i select all the faces at the right arm it looks like it leaves some faces unselected..