If you’re wondering now whether you should commit yourself to studying for another 4 years …
A PhD is NOT “studying”
Contrary to what everyone outside academia thinks: doing a PhD is a JOB. You may do some modules (in some countries), but that’s a very small part of it. The main job of a PhD student is to push the boundary of human knowledge (in our own tiny way), and the majority of your time will be spent reading papers, teaching yourself things you read in those papers and trial and error. At the end of your PhD, the idea is that you will be the expert in the niche that you have carved out for yourself, and all the learning and experimentation you do during your PhD is to take you there. You will have to be extremely self-motivated and function well in uncertainty. If that doesn’t sound like you: Run!
A PhD is NOT for the faint of heart
It’s tough. There will be times when you feel like you’re just going around in circles, making no headway and that you should just give up. What will sustain you through all this is your love for finding out new things, no matter how small. If this doesn’t sound like you: Run!
A PhD graduate is NOT (that) well paid
Assuming you are going to continue in academia, you will probably have to do a post-doc (also NOT studying) after your PhD. Every post-doc is different, but at the start, you can expect to be paid, per month, around US$4000 in the US, GBP2500 in the UK, A$/NZ$5000 in ANZ and S$5000 in Sg. This will go up as you do more post-docs, publish more and progress towards an Assistant Professorship; but at that point your timer really starts: tenure in 10 years or bust! Considering you spend another 4 years to start at this point, if you want a high pay, go into investment banking (or learn to count cards). So if you’re in it for the money: Run!
Job opportunities do exist
The jobs when you graduate will be there. Some areas do have more jobs than others, but if you are willing to be flexible and try new (somewhat related) areas and able to travel to other countries, you will find jobs.
A PhD is rewarding (or it will be when it’s done)
At the end of your PhD, you will have a “Dr” in front of your name; but by that point, you’ll be so embarrassed by it, you’ll just ask everyone to call you “Bob” (or “Jane”) anyway. What’s really worth it is that you will have a body of work you can call your own, and you will have bragging rights of having pushed through all the cow crap to finally get there because in the end …
There is no nobler pursuit than the pursuit of knowledge
(yeah, okay, if you say so)