Why Revelation is Cyclical?

It is commonly observed that Revelation is cyclical, covering the same period (normally from Christ's 1st to 2nd coming) from different perspectives. The most obvious example would be the three sets of sevens: seals, trumpets, and bowls. But why is it cyclical? How does cyclicality contribute to Revelation's message?

The book is about revealing what we previously didn't see and covering the same period of time with a new perspective each time literarily enforces that theme. We do not see everything on the first reading of the first cycle; there is more going on. So too there is more going on in the world than we observe on first glance.