What is IMPORTANT is to learn from what we see.

Looking reasonably closely I can not see any other support under the vehicle on the High-lift Jack and the gentleman has his head in the wheel well.
The thing to think about is what would happen if the jack slipped while he is doing what ever he is doing under there .
I believe that it is good practice to stick something under the chassis to prevent you being hurt if things go wrong.
The most obvious choice is the wheel that you have removed.
Constructive coments please.
If you want to Tread jack this topic please copy it to a new topic in off topic .Thanks