Why is the term ‘silly’ associated with some fielding positions?

Why is the term ‘silly’ associated with some fielding positions?

The term ‘silly’ is normally used in combination with other fielding positions to indicate a modified position. The fielding positions with which it is used are point, mid-off and mid-on, which are considerably farther from the striker. But associated with ‘silly’ it denotes a position which is closer to the striker. Simply said, the term refers to the ‘silliness’ or stupidity of exposing oneself to such danger. In olden English, ‘silly’ also meant ‘defenceless’ – so in that sense too, the usage is appropriate