I did this, and unfortunately your fears became reality for me. Like you said, I only had a vague idea of what I wanted to do (including traveling, starting my own company, continuing education, side projects, etc). Almost 2 years into it I ended up just barely dabbling in each. I traveled for a few months, worked on some side projects, and learned some new things, but didn't really do anything "big" or traditionally "worthwhile" with my sabbatical. I look at my friends and colleagues who in this time period have gotten promotions, new jobs, MBAs, etc and I start feel like my time has been wasted. People keep telling me that once I join the workforce again that I will look back fondly on this time, but right now I definitely don't.
The most frustrating thing I have experienced is that society in general is still not accepting of people taking "sabbatical" in their 20s. While about 10% of people think it's cool that I quit my job and am flying by the seat of my pants, the other 90% hear that I'm unemployed and treat me like a pariah. It's been very eye opening to me just how linked your personal identity is to your job. And I don't mean job as in "I am a programmer", but specifically the actual name of the company you are employed by. I've had people be very interested in conversation with me at social events when I talk about work-related things, but when I actually say the words "I don't currently work anywhere and am taking some time off", those same people have literally picked up their drinks and walked away.
It's particularly bad with recruiters now that I'm ready to start looking for a new job again. Even though I left my company on extremely good terms (they literally begged me to stay!), recruiters seem to see that I left [insert major well respected company here] and assume that I must been have fired. Most still seem to think Google et al are some extremely coveted workplaces and can't imagine that someone would willingly leave them. It is a very tough hurdle to get over.
The most frustrating thing I have experienced is that society in general is still not accepting of people taking "sabbatical" in their 20s. While about 10% of people think it's cool that I quit my job and am flying by the seat of my pants, the other 90% hear that I'm unemployed and treat me like a pariah. It's been very eye opening to me just how linked your personal identity is to your job. And I don't mean job as in "I am a programmer", but specifically the actual name of the company you are employed by. I've had people be very interested in conversation with me at social events when I talk about work-related things, but when I actually say the words "I don't currently work anywhere and am taking some time off", those same people have literally picked up their drinks and walked away.
It's particularly bad with recruiters now that I'm ready to start looking for a new job again. Even though I left my company on extremely good terms (they literally begged me to stay!), recruiters seem to see that I left [insert major well respected company here] and assume that I must been have fired. Most still seem to think Google et al are some extremely coveted workplaces and can't imagine that someone would willingly leave them. It is a very tough hurdle to get over.