My mother decided not to switch because she said she was worried about who would fix the power lines if they came down in a storm.......sounds funny, I know, but obviously the split between the production & network side (still ESB) and the supply/customer side (the choices) isn't being made clear enough for everyone to grasp it.
Having explained the process to her, she then decided not to switch because of the perceived palaver over the free electricity allowance for pensioners (it can't be allowed off the BG electric bill, so qualifying customers get a cheque payment every 2 months from SW).