Why is it highly disliked (Makruh Tahrimi) to pray while resisting the severe urge to urinate or defecate?

Disliked Acts in Prayer Part 2: Environmental and Posture Dislikes

• Because it physically breaks the ground stability.
• Because it completely destroys concentration and internal humility (Khushu').
• Because it is only allowed during the night.
• Because it changes the direction of the Qiblah.