Who were the Spartan slaves most afraid of that they wouldn't rebel?

The Spartan slaves, known as helots, were most afraid of the Spartan citizens themselves, particularly their military and the brutal enforcement of their authority. The Spartans maintained a culture of fear through harsh repression and frequent displays of violence against the helots to prevent rebellion. Additionally, the fear of the consequences of an uprising, including brutal reprisals and collective punishment, further dissuaded the helots from revolting against their oppressors.