Before you start learning something new, read this

How many times, in your life, you think about your skills and abilities and assert: “It’s time I learn something new!”, and of course your pick is based on a specific need you might have at that moment.

I had the same thought just yesterday, when I realized how much Java is being used inside my company, and how little I remember about writing Java code. “I should learn Java again!”, I said, adding “And hopefully, become a great Java coder, better than I ever was!”.
I kept convincing myself, considering that Java could also be used to develop mobile applications on Android. That’s a plus! I have always wanted to build something complex on Android, instead of the few little demos that I built over my last two-three years at Amazon Web Services (AWS).

But then, something else came to my mind: the concept of the Half-Life of knowledge.

Half Life of Knowledge

Wikipedia explains it very succinctly here, but here’s my own (layman) explanation:

Whenever you invest time in learning something, from the moment you have learnt it, the value of what you have learnt, and how much you recall about it, both start “decaying”, or losing value.

As a consequence, I find it very wise to consider the following:

If you want to learn something new, before you even start, consider the Total Lifetime Value (TLV) of your investment in learning it, and decide if it’s worth it or not.

To simplify, let’s consider the following example:

1. I decide to learn some advanced Java, and I dedicate 100 hours of time to it.
2. After these 100 hours (let’s say over the course of three months), I have become a better Java Programmer than I was before starting.
3. I then use these new skills to write an Android application. I also use these skills with candidates in the next four technical interviews I am in.
4. However, a year goes by, and there’s no other use of these skills.
5. After a year, and without any extra time dedicated to refresh these new skills, and retain them, I have lost about 80% of what I had learned just a year before.
6. I might use these skills later in life, but let’s say that most of the value of these new skills is now lost.
7. I have essentially spent 100 of my productive hours to learn something that had a very small Return On Investment (ROI).

This stupid, simplistic example suggests that, if we treat our time like a precious, finite resource, and we pay close attention to how we spend it, we might avoid falling in the trap of “Let’s learn this cool thing”, which could be exciting but could be a poor use of that time.

What do you think? Does this resonate with you? Do you have any examples to share?