In my early twenties, I often told my mother, "I'm never going to stay home when I have kids." The culture of the early 90's promoted women focusing on their careers and breaking the glass ceiling. I pictured myself being a pathbreaker in the career world. My picture of being at home was tied up in visions of endless cooking and laundry, and the disadvantages of depending on a man's income. I wanted a husband and children eventually, but I honestly couldn't envision even remotely wanting to be at home.
DH and I both came from very traditional families -- our mothers worked inside the home and our fathers outside the home in careers that required a lot of hours. Sure, my dad would vacuum when asked, and he ironed his own shirts, but it was clear that my mom was "in-charge" of the household and the kids. When I was in middle-school, my mom started working part-time as my dad's secretary. My dad did typical things like playing ball and also played a supporting role in reinforcing character and values. DH's mom did the accounts and payroll for his father's business in the construction industry.
I excelled at math and science, chose to pursue software engineering, where women are still a minority, and ended up specializing in a part of the field that is very close to the hardware. In the places I've worked, women made up maybe 10-15% of the engineers. Neither my mother nor my mother-in-law put any pressure on me to pursue a traditional path. In fact, when we were dating, my then-FMIL told DH to make sure he respected that I was a "career girl", and to support me if I chose to keep working after kids.
All along though, I listened to the voices in the media that talked about the stresses of trying to have it all. How emotionally wrenching it can be to leave your infant in daycare. How exhausting it is to work a full time job and then come home and do the second shift.
I worked for 12 years before I had a child. In that time I was on some fairly intense projects, where I hardly had time to do laundry and was pressured to eat dinner at the office. I often thought, "How in the world am I going to do this when I have kids?" (And frequently I wondered how I was going to even find a husband while working so many hours!) After a number of years, I found that while I liked my profession well enough, I didn't LOVE it. Periodically I would scratch my head over how to find something I was more passionate about.
So when things finally lined up in my personal life, and I was married and expecting our first child, I took stock of my options. Working full-time, sending my child to daycare, then doing the second shift just sounded like so much stress. I wanted to ENJOY this phase of my life, not just get through it.