#2 The part-timer wouldn't improve ratings constantly

Some think that WWE's future at Fox might be a reason for them in considering Brock to be a long-term champion in place of the current title holder Kofi Kingston. The cash-heavy deal that they have with the gigantic television network is subject to be canceled if their ratings don't improve. In such a case, it looks likely for them to take that route.
The episode of RAW that followed the Money in the Bank had a boost in ratings. Thus it is obviously clear that Lesnar has the ability to get the audience hooked on to the blue brand too. However, there is a small problem in that. If Lesnar becomes WWE Champion the ratings would improve on SmackDown Live for a particular season when he appears.
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The Beast Incarnate might likely take the title with him into hibernation mode, which would leave the rest of the roster without any motivation. Kofi Kingston thwarting a successful cash-in by the Beast looks unlikely. However, it is much needed to build a credible champion for Smackdown and a short storyline between the both of them when it starts airing on Fox.
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