Because their life revolved around war. There was a political king, and a war king at all times, and the war king could have easily had the political king killed he wanted to. It wouldn't have a happy ending, but it was certainly a big possibility. The war kings weren't exactly known for their intelligence outside of battle.
created many aspect of society
The revolt (which was crushed) caused Sparta to realise that they needed an army ready for battle the entire time if they were going to control the vast number of Helot slaves. So all men (and women to some degree) trained for battle and Sparta became the most feared fighting force in Greece. Answer And if the question is refereeing to revolts in mid 5th BC, after the great earthquake, than the answer is revolt destroyed the system completely
Constant threat
They were a threat because the people could revolt and this could lead to the dissolution of the monarchy, if not counteracted.
There was a bloody and violent slave revolt in the province of Messina in 640 BC
The constant hurricane threat.
constant sewage from inhabitable places.
Constant threat
they had help from Athens's, Sparta and a few other city states
Sparta's population was mostly slaves, and their economy depended on slave labor. A slave revolt would certainly be economically devastating, and there was a distinct chance that the slaves would win and overthrow the Spartan government, so obviously this was always something Sparta was worried about.
Earthquakes
The company received a threat of legal action from a competitor.