A lot of PhD students get lured into PhD programmes only because it appears to them as a very interesting and appealing field which they see many in their social circle and they feel that having a doctor degree would give them plenty of employment opportunities in both academics as well as industry.
Often to lure students into a PhD programme coordinators and universities may tempt them by saying that there would be up teen employment opportunities available for them and how there package would at the least, double up by the time they complete their thesis. You may even here a lot if examples related to this often. However, even if you want to believe this or even if the statistics may be true, know that it would take at least 5 to 6 years for your PhD to complete you programme and the similar market analysis may not be applicable then and your industry may have altogether different demands or requirements which may not line up with your PhD.
In addition, if you see statistics with people climbing up the ladder of success after completing PhD, you may also find statistics about people who quit their PhD midway but still end up getting phenomenal success and start earning good even at the time you are busy completing your dissertation to be able to earn well in the future.
The gist of the matter and discussion here is never enrol into s PhD programme because you think it is a hot topic now, you never know how “hot” it would remain in the future by the time you have completed it.
So don’t go into a field just because it is hot right now. It may be very cold in a few years from now.
Every industry, topic and field if study has a life cycle like all other things. The wise scholars are those who jump into a particular research when they feel that it is still at a nascent stage and they can predict and foresee it becoming a more relevant and hot topic in the times to come. Whatever contribution they make in this area remains to be novel and innovative. So they become the ones who exploit the opportunity as compared to those who enter late.
Success though is a contribution of luck and insight but being proactive is very important and you must only enter into a tough and challenging PhD programme when you feel that you have enough time in this field to show your mettle and use the degree to your materialistic and intellectual intellect.