Ever find yourself wondering why millennials seem to be so happy with the successes they have achieved in their work and lives? Turns out, this young and rising generation may have been one step ahead of us all along.

It all begins with how millennials define success in comparison with how we have normally thought about it. Beforehand, we measured success by the material possessions we could afford to buy: How successful we were at college led to how good our job was which determined how expensive our house and possessions would ultimately be. What's different now, however, is that we are no longer looking at success in the same ways.

Instead of seeing prosperity as wealth, or material possessions, millennials measure success much more by experiences--by stories, if you will. Perhaps due to social media and the increased documentation of life experiences, we now value the things we do--rather than the things we have--much more.

Millennials have always known that.

How well someone is doing is determined by the quality of their last internship, the memories they kept from their last trip, the level of intimacy they share with their closest friends. Success is now much more about where you went on Friday than what you drove in to get there.

Although arguably an unhealthy, competitive lifestyle, comparing one's experiences prioritizes different things, in regards to one's happiness, than comparing one's material artifacts. Millennials are, instead, often obsessed with staying in the know, remaining in constant communication with everyone we know so that we don't miss out on anything.

Yet, at the same time, this pushes them to do more than they might have ever done alone. With more of an experience-based approach to happiness, millennials are able to find reasons to throw themselves into situations they might never have otherwise; they have greater incentive to take risks, to attempt making new memories--or at least try to.

The secret behind millennial success and happiness has been something so simple that it's been easy for us to miss all along: Focus on the now. Not the before, and not the after.

Make experiences so that you have stories to keep--and know that they'll always be more fulfilling than anything else you could possibly hold.