The needle is very, very sharp
Very true, and very relevant to this discussion. What is it that people fear from needles ? Pain, of course !
Yet, if very sharp, and if used correctly (very important, that) you should actually feel little or nothing. I saw a pilot only yesterday who needed his cholesterol checking since this was the first renewal after turning 40 years. His eyes were shut, and he asked me when I was going to stick the needle in - - it already was ! !
Very similar to the exceptional sharpness of freshly broken glass. If you have ever dropped something of glass in the kitchen, while clearing up you cut yourself -- feel no pain, but see the blood first !