I believe that we lose our legs exactly through having cuts that don't heal. If you are on top of a situation like that and go to the doctor immediately, I think that you have very good chances. I think that many people are "off the ranch" and may not go to the doctor, nor test their BG nor take medications regularly, e.g. T2 whose rx runs out and they blow off getting more for a while. Then something innocuous happens, stubbing toe, a blister, cut or whatever and faced with the choice of going to the doc who will probably yell at them, they try home remedies or maybe don't do anything about that either. There's a possibility that when something goes south, particularly in a person with uncontrolled diabetes (I'm saying the person is not doing much to control it, not because their doctor labelled them as such, although I believe that's what the designation is for, not someone who works hard at it but is > 7.0 or whatever the medical "goal" is!), that an infection can set in and you can lose toes and limbs.
The first time I ran > 30 miles/ week, it was cold out (January 2011 I think, maybe 2010, I don't recall exactly...) and, accordingly, I wore extra socks that beat up one of my toenails which turned black. I was alarmed and went to the doc. Both at the convenient care place and the subsequent podiatrist were effusive in saying "good job getting this checked out, it shouldn't be any problem but you *always* want to get these sort of things checked out..." and rx'ed some sort of strong antibiotic and took the nail off to fix it. Not a big deal but I interpreted their reactions as indicative that they'd seen worse things before, that many not have had a pleasant ending?