Optimizing is a complex problem.  Deciding what to do about our coming baby's nappies (US translation: diapers) highlighted the need to understand what is being optimised and what the trade-offs are.

Currently my wife and I have been discussing what to do about nappies for our coming baby.  I'm still dealing with this at a numerical rather than the emotional level as I'm still dealing with the sock that there may be over 5000 nappies in the first few years of a child's life.  While disposable nappies have the attraction of convenience it just feels bad to throw that many things out.  There's lots of evidence that disposable nappies represent around 2% of landfill and are generally evil as this clearly biased site  demonstrates.

I spoke about this problem with a good friend of mine who studied Computer Science.  He was a father himself and didn't like the idea of not using disposables because of landfill.  He came back to me last week with the following comment:

"While it is true that nappies do contribute to a small amount of landfill, there are great contributors to landfill such as kitchen waste.  As a Computer Scientist if I was trying to optimise something I'd start with the area that I could have most impact"

I liked my friend's thinking and told it to my wife, who said "yes, but choosing a cloth nappy washing service is a simple decision that is easier to implement than having to think about all of our waste".

I'm not sure which approach is "right" (we'll be using a cloth service for the first month) but to me it highlights that optimization is a complex problem that involves understanding what to optimize and what the trade-offs are.