The reason for this is there is a major bug with Google Scholar that just doesn't pick up some names; yes of course I am one such academic, but if you search you will find numerous examples.
So unclickable names may be because the authors profile is not set to public, or the simple bug described below.
Naturally other answers will all be about making it public etc etc, but in fact, after many hours of investigation, there seems to also be a simple bug that no one has a solution to. Of course I have reported this to Google with out response. It seems to be because whatever you do some names are not indexed; so the profile exists, but is just not linked.
Try mine for example; search for my name you find my papers, but no indexed (clickable) name and no profile. One can only find this with a direct link, which one can of course put on your website etc
Another example is here Another example, but there are many.
The reason for entering this as an answer, rather than a comment is that there are many academics, and authorities that judge academics by their Google metrics and simply do not understand that these unfixable bugs exist. "S/he can't be a reputable academic because doesn't even have a Google Scholar Profile". Metrics are never a great way to assess one another anyway, but it is essential that everyone recognises Google Scholar is buggy and unreliable.
Please don't anyone respond with "click make it public". Obviously we have all done this. I am astonished that people assume, despite evidence and people's experience to the contrary, that this is the one computer system that has been invented without bugs.
screen shot of the public tick