I definitely cannot do this any more.
Even when I was on a property and had a commercial whipper snipper, I had problems, though eventually I could get it started.
Now, after have smashed a vertebrae, I am unable to do things like this, so bought a small electric lawnmower yesterday for a small patch of grass.
I do not know why there are not more key start mowevers being invented, and whipper snippers often are a poblem.
Pull cords should be replaced.