Confusing Design Hotel late check out benefits webpage
 

https://design-hotels.marriott.com/member-benefits/

The white banner gives the impression the main purpose of this page is to communicate Bonvoy elite benefits at Design Hotels as it spells out Benefits You Get vs. What's Not Available.

Last bullet point under Benefits You Get:

• 4pm Guaranteed late check out for Platinum Elite, Titanium Elite and Ambassador Elite (based on availability at Marriott Bonvoy participating Design Hotels™, convention and resort hotels)

In regards to late checkout, is it guaranteed or is it based on availability?

Red bolding YOURS.

Simple. "4pm Guaranteed late check out" is the name of the benefit, given to those eligible for it. It is based on availability at Design Hotels. Just as it has long been understood to be based on availability at resort hotels.

Have fun with the word "Guaranteed" in the benefit's name, but the wording is very easy to understand.

It absolutely makes no sense. This page explicitly informs about Elite benefits at Design Hotels, so the wording used is confusing if not misleading.

Another page with wrog information about Design Hotels:
https://design-hotels.marriott.com/member-benefits/faq/
=> Design Hotels™ member hotels that are Marriott Bonvoy Partner Hotels booked through any official Marriott reservation channel will participate in Best Rate Guarantee (BRG) program in a limited capacity. This changed months ago.

Depends on the brand. At Design hotels, it is not guaranteed.

The language in the T&C is clearer:

It’s pretty clear its guaranteed everywhere but the hotels/brand in brackets where it’s based on availability.

Design hotels is based on availability, I assume this is because they are generally very small hotels with limited room numbers and if successful high occupancy so late checkout is trickier.