You read it right.  It is not true that your life only begins when you reach 40 years old.  I'm near 40 and this is my realization.  Don't get me wrong - I have a beautiful life though.  Once, I wrote about me being in my 30s here.

Stop being pessimistic about it. This is the stage of your life that is almost done. Considering that life expectancy these days is slim, say most people die at the age of 60; you're lucky enough if you reach 70. So you only have a few years left living. Another 10 or 20 years seems long, but life is getting fast paced.

There's nothing much now you can do with your life when you reach 40 years old. At this time of you're life once and for all be realistic. Don't live your life like there's still tomorrow full of hope.
You must have a good sense of wisdom by the time you reach 40. your life isn't like the way it was before when you're younger. Make yourself aware of this.

It's not being harsh to oneself thinking life really is not a new beginning when you reach 40. All you have to do is wake up from a dream that never will be happening to your life.

When you're 40 years old, your body is not that energetic as it used to be. Every part of your body deteriorates and it will continue the moment you turn 41 or so. Your mind is not that sharp anymore as you age. This is the time of your life that you lose most of your productive time. All you want to do is rest and rest after a week of work.

You are mostly not interested doing new things in life. This is the truth about being 40 years old. You don't care to start anything else. You only continue to do whatever is necessary and needed. It is a customary day to day life only.

So you must not think that life begins at 40. It is full of imaginative thinking only.