Adding a time-lock to a Piggy Bank helps to remove the temptation to spend your savings (if that is the intent of adding it) because not only is it more difficult to see what you have saved, but you also know it will take at least 7 day to withdraw funds if you really want to.
Time-locks can also be used for peace of mind.
Sadly there are bad actors in the world looking to socially engineer and scam others, or possibly steal your phone. If you have added time-locks to your most important savings (that you don't need immediate access to), you can have peace of mind that should the worst happen then you have 7 days to sort things out before any money could be transferred.
In addition, you even have the option with time-locks to notify a trusted person (e.g. business partner, family member or good friend) that you have instructed a withdrawal on a time-lock protected Money Pool or Piggy Bank. No transaction information is sent, the trusted person is emailed alerting them that you have made a transaction from an account which you do not normally withdraw money from. This gives enough time for your trusted person to call you, and check that you really intended to instruct the withdrawal. This can offer a huge peace of mind if you have concerns about social engineering scams.