If I am concerned about my jawline, should I get Shrink done on my entire face?

I am most concerned about the area under my chin and my jawline, rather than my cheeks or cheekbones.

However, when I looked up Shurink, I found that many people get it done on their entire face, so...
I became curious if I absolutely have to do the whole thing.

Those who have received treatment focusing only on the desired areas
Did you actually feel like your jawline became more defined? 🙂