Insurance stakes are for those who are willing to forego 10% of their staked balance in exchange for having the ability to cash out of the stake at any time. This is good for those who want to enjoy the higher interest earning of a longer stake but may be nervous about potentially needing to cash out their position before the stake ends.
Example: You want to stake 10,000 SWAPP tokens for 2 years in an "insurance stake". 10% of your balance (1,000 tokens) is subtracted and immediately distributed to all other existing stakers proportionate to their amounts staked. The remining 90% of the original staked balance (9,000 tokens) remains invested and earning interest until the maturity date (when the stake ends). In exchange for relinquishing the 10% of tokens invested, the staker is allowed to cash out that stake at any time with no additional cost or penalty.