And that question being common is exactly why many non-profits have focused on reducing "overhead", actually making the organisation less efficient, because having e.g. medical workers do their own administration doesn't get listed as overhead, whereas hiring a secretary does.

With charities in general, it'd be better if people focused on results more, rather than on how resources are being allocated. Luckily, that idea has been gaining more and more traction, e.g. GiveWell.