Combination of not wanting to give up under hooks which generally is the more dominant position in the clinch and secondly IMO its got a lot to due with leverage, typically when we see it utilized we also see a substantial difference in height where the added leverage can help make it more effective.
"If you get hit and it hurts hit him back you not knocked out yet."-Joe Doerksen
The Toxic Terrors (FFL)
Demetrious Johnson*Eduardo Dantas*Emanuel Newton*Will Brooks*Michael Page