The 70/90 Rule

I was having a conversation last week with a good friend who works in the financial services sector. We were discussing technical debt, and the tendency of certain teams to want to do everything themselves. He described some colleagues in a team that is tasked with managing a large data pipeline for calculation of risks in a particular market. This is central to the bottom line of the company. Oh, they also used to run their own mailing list server! This was in an organisation that had it’s own very functional and well behaved central mailserv setup. The reason they gave for wanting to run a separate mailing list just for that team was that they wanted the ability to search the archive, but the real reason is that they had fallen into that trap of wanting to roll their own thing. (It turned out that the search functionality had broken back in 2012, but no-one had noticed).

When recounting this to me, my friend remarked

I’d much prefer to use an off the shelf solution that did 70% of the job, than custom build my own system to be able to do 90% of the job.

There are two really smart observations here. The first is that we never get to 100%, we can always think of things to improve on, so rather than going for 100% it’s a better strategy to identify what parts of an imagined system are going to create real value.

The second is that we should be mindful of where our effort is going. That thing that we are customising and configuring - workflow, or emailing list, or phone setup, or multi-core cluster, how much of that effort is helping us get the actual job that we want to get done? How much of it is satisfying our desire to tinker with the solution, rather than engage with the job?

For sure there will be tasks that we need to go all-in on, however we should be really careful to make sure that these are the ones where we are adding the most value.

I got to thinking about my blog. Since the start of last year I’d not been happy with the design, it was not responsive, the typography was messy, and the font a bit too small for my tastes.

I started to tinker.

I took inspiration form Martin Fenner’s’blog, and all of a sudden I was looking at getting into a world of custom CSS, and Jekyll extensions.

Then after the conversation with my friend I stopped and asked myself, is there an off the shelf solution that gets me to 70% of my needs, and that requires absolutely minimal configuration.

I did a quick google for “Jekyll themes” and within an hour had adopted a version of the hyde theme.

The original customisation task had ballooned so much that I’d created a trello board to track all of the things I wanted to do. After opting for the off the shelf solution I was able to drop most of these requirements, and just get back to focus on writing for the blog, rather than worrying about configuring the blog.