Are there any economic theories around the concept of companies focusing on that which is easier to calcuate? A lot of the organisations I have worked for have focused on that which is easy to calculate.

For example, direct cost savings are often easy to calculate, but analysing the wider implications of a cost cutting exercise are complicated.

A company might save money on their IT budget if they reduce the number of printers they use and this is relatively simple to calculate. However, the implications for productivity of having fewer printers is much more complicated and is often ignored (in my experience).

Are there any economic theories that investigate this effect?
Your question is ultimately one about information flow in networks under conditions of imperfect and incomplete information. I like your distinction between "easy" and "hard" to calculate - it's a good rubric for problem classification.

I believe that work being done on complexity theory and information flows can help shed some light on how to think about the issue. Cesar Hidalgo is a leading thinker in this field and has assembled some very interesting tools in the context of global trade (the Atlas of Economic Complexity being one). At the level of organizations, there would be an additional layer of complication arising from behavioural anomalies in decision-making that tend to bias human beings in favor of decisions cast in terms of simple data sets with clear narratives. This is the other side of the coin to Nassem Talib's "narrative fallacy", and of course, any study of behavioural biases must also include some time spent with the work of Kahneman and Tversky.