I particularly like the mention that a CS PhD isn't about "novelty" or "freedom", and I've found this to be a common misconception that new CS PhD students make. Another common one I will bundle in there is "making an impact on the world"; I cringe when a new PhD student tells me they chose to do a PhD because they wanted to change the world. There are so many better ways....
This is a great point. There are many avenues where one can invest time+money to make a positive impact on the world, yet "doing a Ph.D" is unfairly held up on a pedestal, even though there is no hard science showing that grad school is a prudent way to attempt such an endeavor.
Edit: adding examples of ways that are less sexy, yet way more likely to be measurably impactful (in a positive way)
1. Teach high school,
2. Volunteer at your local soup kitchen (do it for 2 years -- less than half the time you'd spend in classes for quals),
I particularly like the mention that a CS PhD isn't about "novelty" or "freedom", and I've found this to be a common misconception that new CS PhD students make. Another common one I will bundle in there is "making an impact on the world"; I cringe when a new PhD student tells me they chose to do a PhD because they wanted to change the world. There are so many better ways....