With a mortgage you also have an opportunity of accumulating a loss.

A really simple calculation with the numbers from http://homeguides.sfgate.com/calculate-30-year-mortgage-bala... I will be nice and assume that the monthly cost of renting is equal to the monthly mortgage payment. Usually renting is cheaper. I'm ignoring the mortgage interest deduction, but also property taxes, homeowners insurance, maintenance, etc.

After 5 years of renting you have: 5 times 12 times -600 = -36000. After 5 years of owning you have: 5 time 12 times -600 + your equity. your equity is $100,000 - ~$93,000 + difference between what you bought it for and what you sold it for. And that last term can easily be negative. It only takes a 7% decline in value to wipe out the first 5 years of principal payments. If your property declines in value 10% and you sell after 5 years you come out behind.

The numbers for 10 and 15 years respectively are 16% and 29%. Now consider that the average home value in places like Stockton fell over 50% during the great recession.

It depends on your locale and employment situation. Many home owners are "house poor." Their only asset is their house, and they have no savings or other investments. I moved to a locale where I could make 3-4x what I could in my hometown, rented for 10 years and with investments, stock options and savings am way ahead of where I would be if I would have bought a house where I started out. My parents on the other hand are trying to sell their house for almost the same price they paid for it 15 years ago. My cousins with homes are not financially doing well at all.

If I would have had the money and foresight to buy the brownstone in Brooklyn that I was renting, I wouldn't have even had to bother with the working and saving for 10 years part, but you don't need to rub that in on a Saturday morning.

I'm not the parent but I have to say that's an over-generalisation. The costs involved with buying mean that the balance between renting and buying can be tipped firmly in favour of renting even for 10+ years. I ran several calculations earlier this year as I was considering buying for the first time (it seems easier for those who are already on the ladder) and this turned out to be true for me. I pay an incredibly low amount of rent for Silicon Valley's current rates.

Given the area and amenities I want from a property, I save significantly more money renting and can live somewhere I actually like; unless I decide to commit to the country for 10+ years -- and I would lose my entire cushion of savings for startup runway funding in the process -- renting makes a ton of sense, even though at the base level the equation of "paying money for someone else's mortgage vs paying money for my own" seems a no-brainer.