Why do you think they're vindictive? Why do you think servants leak out information about where your gold is, and how to get into your house to robbers? Why do you think they have zero sense of loyalty to you?
If their job is so bad that you have to get on their case, then don't hire them and do the work yourself. I assure you, cleaning a toilet is not that bad. It is your own waste, after all.
why do these people do such things?? and if u dont trust them, why hire them?! Give them money, send them to school.. be their guardian or something...