It's just the way they are. This is an Achilles heel with the design that won't go away entirely.
When they work right, they are a generally reliable carburettor and are easy to work on once you learn which bit goes where.
The ptrimer bulb most certainly is a benefit. Only the other day with my inward facing G4, it wouldn't kick over until I went to the effort to push the primer bulb hiding behind a couple of times before it fired up first pull.
