Having the right expectation is one of the ways that you can reduce frustrations.
This is because you can frustrate yourself by placing your expectation (which is your faith and hope that something will happen) in the wrong person.
For example, if someone has stolen, killed or destroyed something of yours, expecting them to restore it can frustrate you.
To reduce your frustrations, do not place your expectation of restoration on the thief, murderer or destroyer because stealing, killing and destroying are characteristics of the devil for The thief does not come except to steal, kill and destroy. (John 10:10)
Put all your expectation on God even if you are seeking legal redress because He is a restorer for He says, I will restore to you the years that were eaten by the locusts, the cankerworm, the caterpillar and the palmerworm. (Joel 2:25)
Therefore regardless of your specific situation, reduce the frustration of your expectations by looking to see if your expectations match the characteristics of God or those of the devil so that you can know if you are placing them in the wrong place.