The size of hob selected depends on the size of the kitchen the number of household members it serves.
Outside of the USA & some parts of Asia, European standards are typical; hobs conform predominantly to 86 cm or 60 cm width, the length is a standard 52 cm. Other less common widths are 30 cm & anything between 70 and 80 cm.
60 cm hobs are usually equipped with 4 heating zones. For 86 cm hobs, 5 heating zones are common. The bigger sized 86 cm hobs have bigger space in between burners permitting the use of larger cooking vessels.