Keep reminding God's people of these things. Warn them before God against quarreling about words; it is of no value, and only ruins those who listen. (2 Timothy 2:14 NIV)
In this scripture Paul is instructing a young leader, Timothy. The items in Revelation that we have no absolute interpretation of should not cause petty disagreements. We should be able to look at the items we can definitely identify and agree to disagree about the rest. The last three trumpets are events we must be willing to disagree about for they most definitely could be metaphorical.
And I beheld, and heard an angel flying through the middle of heaven, saying with a loud voice, Woe, woe, woe, to the inhabitants of the earth by reason of the other voices of the trumpet of the three angels, which are yet to sound! (Revelation 8:13)
The next three trumpets are known as the “three woes” because of the severity of what happens when they are sounded. It is hard to believe that something could be worse than an earthquake that darkens the skies and meteorites hitting the earth, but the final trumpets will be more fierce than what has come before.