I have heard many times that I should do a PhD only if I love doing research on my topic, and if I cannot imagine my life without research (as research-based jobs mostly require a PhD). Another reason, is out of fun (let's factor out the joy of research). From this post and related comments, and adding other possible points:
- a PhD allows to be surrounded by stimulating, like-minded people, with whom you can bond and create long-lasting relationships
- you get to travel a lot and explore parts of the world
- you can live in an exciting city
- you postpone by few years "growing up", and entering into a repetitive lifestyle
- you have a lot of flexibility in your work schedule
- all of this while getting paid (let's assume a not indecent salary)
- all of this while possibly increasing future career prospects (let's assume I am not working on very exotic stuff)
Now, I like a few topics, but not love them; I find research quite motivating, but not a lot (due to e.g. publication pressure, stress...). That is, I am not someone who is obviously not fit for a PhD, but I don't have that "burning passion" (other personal circumstances: I am a good student with some research work published; I have offers for pursuing a PhD, and have been advised to do so).
Main question: what are the caveats in pursuing a PhD mainly for fun?
Relatedly: is a PhD really that fun, in your experience? What kind of maturity is required from one to have fun and not be overwhelmed by the project? And so on, feel free to add other perspectives.