What's the damage to my donor area after failed hair transplant in terms of grafts lost? (Photos)

If you had over 2000 grafts harvested from the donor area it would likely look relatively thin as it does now (after 12 months).  If you want more grafts you have to understand your donor area will look thinner.  This issue is often overlooked when people choose FUE for harvesting and keep their hair very short.  Many people choose SMP to cover and hide the FUE scars. 

fuepatient212,It is important to include all pictures including: frontal, top-down, side and oblique views to fully assess your situation. Judging from the supplied photos of the donor area, it does appear that there has been extensive harvesting of the donor area thinning the areas severely. I recommend that you have a thorough evaluation by a hair loss specialist to fully assess your options. SMP could be employed to hide the donor scars. Additional graphs could be harvested possibly from the sides and maybe a FUT strip could performed to get additional graphs from the previously harvested area. I would recommend that you consult a hair loss specialist in your area.To start your search for  doctors please visit the American Board of Hair Restoration's website.

Donor hair does not return. For this reason there is a limit to how many grafts can be harvested from a donor site. Typically this limit is set at around 10-15% of the hair in a designated area based on densitometric analysis. Harvesting more than this places one at risk for a moth eaten appearance.A strip procedure is a reasonable option as this will remove the area of harvest (avoiding a moth eaten appearance in exchange for a linear scar).As always, discuss your concerns with a board certified plastic surgeon (ABPS) with experience in hair restoration.

I can't comment on whether your transplant is "failed" without before and after photos of the transplanted area.  From the photos you provide it does appear that the area harvested has been depleted and then some. 
It may be possible to get more grafts from the areas that were not harvested but this would need to be done very carefully.  Although the harvested grafts won't "grow back", it is possible to improve the appearance of the donor area with techniques such as scalp micropigmentation.  I suggest an in-person evaluation with a hair restoration surgeon to review options.

unfortunately one of the side effects of fue hair transplant is donor hair depletion. The hair that is harvested will not return. From the picture, it looks like you already have a depleted donor area and i do not recommend to have a second fue hair transplant. 

The grafts used from the donor area are lost forever. There is no regeneration of the donor area hair, but most people do not deplete the donor area.  2000 grafts can be 30% of the average Caucasian's supply