#4 To draw parallels to the hardcore title
The 24/7 Championship is basically like the Hardcore Championship, except it has a different name and a far worse design. The Hardcore Championship only had the 24/7 rule introduced later on, but it was integral because so many different legends, including women, became champion.
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One thing to note is that the Hardcore title was always contested under "hardcore rules", i.e, No DQ, Falls Count Anywhere, No countouts, etc. That rule hasn't been specified as yet, but it wouldn't be surprising if they do add the rule later on.
WWE probably felt that it was time to re-introduce a similar concept after 17 years. While they obviously wouldn't want to go back to the old name, they likely felt that rehashing the idea in a different form would work.
We've seen situations where the Hardcore title has changed hands multiple times before. If you count the Hardocre Championship battle royal from April 2nd, 2002, then the title technically changed hands 13 times in one night.
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