Why a URL with a question is all the time slower than that with out a question?

I discover a unusual factor. For a WordPress web site, a URL with a question is all the time slower than that with out a question, even no Cache plugin is put in/enabled and no CDN cache is enabled. For instance:

http://www.instance.com/?mytest=sure

will all the time slower than

http://www.instance.com/

Beneath are a few of my take a look at:

1. WP Quickest Cache disabled, URL with a question https://www.fastorslow.com/app/profile/3e875ed3-d45f-54fb-93a2-17466eeb8b79 is slower than the one with out a question https://www.fastorslow.com/app/profile/7ef6f16f-6b0c-5ab6-9f1e-87c0c1a6a1aa

2. With WP Rocket enabled, https://www.fastorslow.com/app/profile/af27e983-1a38-5870-98a3-6cc19825aee1 is slower than https://www.fastorslow.com/app/profile/86d36215-0caf-51d7-b690-d3126a081376

3. One other server, https://www.fastorslow.com/app/profile/9273fb55-adfc-5b8c-aa93-687bc128a95d is slower than https://www.fastorslow.com/app/profile/51062160-fb20-5b0b-97ba-4ce428ba264c

Why?