In regards to why Roman Reigns vs. Brock Lesnar is taking place at the WWE Day 1 PPV, Dave Meltzer of F4WOnline.com noted the following during Wrestling Observer Radio:
“Okay, the deal is that Day 1 is obviously a Nick Khan [WWE President] idea, you know, or the idea of January 1st and the idea is not just this year doing it. The idea is that this will be a regular thing, a new holiday tradition for WWE. January 1st pay-per-view.”
“The idea is to make this one of the biggest shows of the year, you need to establish it. Brock Lesnar vs Roman Reigns is the strongest match they’ve got. So, that’s the match they chose to establish it. The feeling is that Royal Rumble didn’t need it. They’re trying to establish January 1st as one of the biggest shows of the year and so, they’re gonna put their biggest match in there.”
“It is not going to be the last Brock Lesnar and Roman Reigns match, obviously there is still a plan for WrestleMania. So, that’s the basic gist of it.”