Some difficult problems are easier to solve if you don't have to think about them sequentially. One problem in my current work involves getting records from eve

Some difficult problems are easier to solve if you don't have to think about them sequentially. One problem in my current work involves getting records from events one at a time, building predictive algorithms from those, and building another set of algorithms based on those. If you model it sequentially, it takes a lot of work to make sure the right data is calculated in the right order. But you can also model it as a set of lazily evaluated streams, and that makes life a lot easier – because order of evaluation isn't part of the domain, it's essentially an implementation detail. ETA: another way to think about it is that this lets the compiler manage evaluation order by default, while you're free to focus on other stuff (with the option to manage manually if you need to.) This is a similar type of benefit to garbage collection.