> "...You need to know why you want a Ph.D. You need to have vision and ideas and you need to be able to express yourself..."
I've got to stress that this advice is really important.
Especially for people who are considering going into grad school because they're on autopilot or think that it's just a natural continuation of your schooling. That's an easy way to think, but it's not the right way. You can easily lose 6 years of your life in grad school aimlessly this way.
Go into grad school and pursue a PHD because you've got a burning desire to turn one of your good ideas into a breakthrough. If you don't have such an idea based on your undergrad experience, that's already a warning sign that you shouldn't just go to grad school. Another warning sign is if you don't know who (which professor) you want to work for. Grad school is advisor-based in the extreme.
And definitely don't go just because "it's always good to be educated more". That approach will probably leave you disappointed and surprised by what grad school is. As the author mentions, success in grad school is not just more classes. And if you do a random walk because you don't know what you want, you'll waste a lot of time.
Aside from what the author describes in other good points, if you fall into this category of why you "think you want" to go to grad school, do yourself a favor, and get outside your comfort zone and go into the real world of business or a company for a stint. Don't just let yourself go autopilot into grad school because it seems to look like more college. At least have a look outside and try something before you default back to the university.
A few years in a real company taught me much more (and faster), life skills-per-time, than in grad school. Yes, admittedly I came out of grad school with some good technical skills and a whole lot of accumulated knowledge that I put to use today still. But I look back wishing I had learned about real world problem solving and ability to cut the bullshit and get to the bottom line sooner.
Be sure you go in with open eyes. And open them by looking outside first.