basically its not possible that the companies make specific plugs for every car this way they'l go nuts while making different pulgs for different cars cz every country has different cars running in it for example lets assume that they are making different plugs for different cars lets suppose in Pakistan following will happen
fx/alto(old)/mehran wala asking 4 mehran plugs
suzuki daba wala asking 4 suzuki daba's plugs
khyber wala askn 4 khyber plugs
photohar wala askn 4 photohar's plugs
vitara wala askn 4 vitar's plugs
margalla wala askn 4 margalla's plugs
baleeno wala askn 4 baleeno's plugs
liana wala askn 4 liana's plugs
swift wala askn 4 swift's plugs
c its only suzuki havnt touched toyota,dihatsu,honda,mazda,nissan,bmw,merc and the old classic chevorlets,other old classics,sport,vintage cars etc.
so practically making plugs for every single car is impossible so that is why the tip is adjusted at a standard position and the mechanic can adjust it accordingly to the needs of the car.