What's the purpose of the deflector ring?

[Cheapie408]

Mine was chewed up so I can removed all the outter surface and kept the center unit more or less as a spacer so everything can stay. What's the purpose of it? Any downside running without it?

https://www.ebay.com/itm/16458493542...sAAOSwzYpa4qG8

[Keithbaja]

At slow speeds it keeps the exhaust out of the prop bite.... Sounds like you need a complete new prop without seeing it...............