attitude modes why two?

[Suwaneeguy]

Can someone please explain the differences between the two attitude modes?
The S1 switch is marked as:
GPS
Atti
Atti

Why two modes with the same markings?

 

[OI Photography]

The bottom position can be changed to your choice of ATTI or Manual or Failsafe mode. ATTI is the safer option for new pilots (to prevent switching to Manual or Failsafe unexpectedly) so that's the one it defaults to.

 

[discv]

Can someone please explain the differences between the two attitude modes?
The S1 switch is marked as:
GPS
Atti
Atti

Why two modes with the same markings?

I suppose they could have marked it- "Maybe this, that, or the other"