Some people have brought up the idea that people should not enter into a PhD program if they are interested in money. I agree, but the problem goes beyond that. For those of us who are fortunate to find permanent positions doing research, it's actually an amazing life. We're not rich, but we are comfortable and we have jobs that we love.
But, there are relatively few of us who end up with permanent research positions in the sciences. So, let's take my field of physics and consider the situation in the US. Let's imagine two tracks for a student. She's skilled in math, computer science, and physics. She could go into computer science and start working in her field immediately after college. Depending on where she goes, she could make $100K/yr shortly after graduation (ok, a lot of that may go towards rent, but let's just use this as a round number).
Now, let's suppose that she decides to go the physics route. She will likely spend 6 years as a PhD student. Back in my day, I remember making a stipend of $13K/yr. Checking online, these have now gone up to ~30K/yr at a number of institutions. So, at the end of 6 years, that's already a huge opportunity cost. She hasn't bought a house, she probably has few if any retirement savings. Now, let's suppose that she continues for a postdoc for 3 years. Let's say that she makes $50K/yr (it's probably more likely that she'll make $40-$45K/yr, but let's again take a round number). So, at the end of this, she's lost $570K of potential earnings. This is ignoring taxes, but to be fair, it's also ignoring any interest growth that she would have made on retirement savings while working for a company.
Now, one might argue that for quality of life and doing what she loves, this might be worth it if she became faculty at this point. However, the chances of this happening are slim. So, at the end of the day, she'll probably examine her options and in many cases (I have had friends and students that have taken different paths to leave physics--ranging from teaching high school to finance) leave physics to do something else.
So, the question isn't whether it makes sense to do a career in physics vs say a career in CS. It's a question whether it's worth the opportunity cost to do a PhD in physics and perhaps a postdoc in physics before doing something completely different. There are of course some areas of physics where people are able to find industry positions doing physics, but this is often not the case...
I think that departments need to be upfront about this and provide students with training opportunities to do other work if they are interested in doing so after their PhD...
The calculation may be different for those in engineering fields...
But, there are relatively few of us who end up with permanent research positions in the sciences. So, let's take my field of physics and consider the situation in the US. Let's imagine two tracks for a student. She's skilled in math, computer science, and physics. She could go into computer science and start working in her field immediately after college. Depending on where she goes, she could make $100K/yr shortly after graduation (ok, a lot of that may go towards rent, but let's just use this as a round number).
Now, let's suppose that she decides to go the physics route. She will likely spend 6 years as a PhD student. Back in my day, I remember making a stipend of $13K/yr. Checking online, these have now gone up to ~30K/yr at a number of institutions. So, at the end of 6 years, that's already a huge opportunity cost. She hasn't bought a house, she probably has few if any retirement savings. Now, let's suppose that she continues for a postdoc for 3 years. Let's say that she makes $50K/yr (it's probably more likely that she'll make $40-$45K/yr, but let's again take a round number). So, at the end of this, she's lost $570K of potential earnings. This is ignoring taxes, but to be fair, it's also ignoring any interest growth that she would have made on retirement savings while working for a company.
Now, one might argue that for quality of life and doing what she loves, this might be worth it if she became faculty at this point. However, the chances of this happening are slim. So, at the end of the day, she'll probably examine her options and in many cases (I have had friends and students that have taken different paths to leave physics--ranging from teaching high school to finance) leave physics to do something else.
So, the question isn't whether it makes sense to do a career in physics vs say a career in CS. It's a question whether it's worth the opportunity cost to do a PhD in physics and perhaps a postdoc in physics before doing something completely different. There are of course some areas of physics where people are able to find industry positions doing physics, but this is often not the case...
I think that departments need to be upfront about this and provide students with training opportunities to do other work if they are interested in doing so after their PhD...
The calculation may be different for those in engineering fields...