But not all tasks can be made bite-sized. Or more specifically, sometimes the bite-sized pieces aren't "complete enough" to be a valid unit of work to be nicely

But not all tasks can be made bite-sized. Or more specifically, sometimes the bite-sized pieces aren't "complete enough" to be a valid unit of work to be nicely wrapped up and finished during a sprint. What happens as a result, is that more major tasks never get sufficient priority to actually happen. This can easily lead to an incremental "refuctoring" of the code base, where you have a lot of individually-nice bite-sized tasks that, in aggregate, turn the source tree into a total mess.