I may point out that your original post stated " waist of time".
Waist ?, as in the area of a persons body just above the top of the pelvis ? (and narrowing sections in many other applications too many to list) but never in the context of 'time'.

As for "waiste", unless you are a student of 'Ye Olde English', stop wriggling and admit that plonker* is a description that fits admirably.
* Look that one up in your Oxford.