When I retired my s3's and s5's I wasn't making enough money with them to pay for the electricity; or so I thought. If I had left them turned on longer I might have been paying $1.15 in electricity for $1 worth of BTC that today would be >$7. Kick me in the #@%*! I save most my coins so it really hurts. I guess if I sold them every week/month it wouldn't have mattered.
I sold them (s3's & 5's) to some teenage kid on craigs list. I should have waited to retired them only when I needed room on my panel. Live and learn.