Given all the tips floating around out there, you could spend hours, days or even weeks nailing down the perfect productivity system. What's the right way to start and end your days? Does your to-do list need a bit of gussying up? Should you keep a journal and, if so, what kind?

Questions like this barely scratch the surface of the advice on offer--I didn't even mention the seemingly endless parade of apps and gizmos offering to help you get more done that you could test out and evaluate.

The first and clearest danger of all this (often genuinely helpful) advice is that busy entrepreneurs will get bogged down spending masses of time perfecting their systems for getting things done rather than, well, getting things done. But perhaps, when it comes to productivity, another less acknowledged pitfall also lurks--not that you'll tweak your system too much and often, but that you'll stick to it too rigidly.

That's the danger flagged up in a thoughtful post on blog Cube Rules recently. In it Scot Herrick pulls back the curtain on a little acknowledged secret about task management and productivity. "How you organize yourself will change drastically over time--and not much time at that," he warns.

When it comes to productivity, the only constant is change

A project manager by trade, Herrick passes on a bit of wisdom he's learned through personal experience. Whatever task management system you adopt is almost certainly context dependent. Change your project, your lifestyle, your collaborators, or any other salient variable, and your system for getting things done is going to need serious adjustment.

"I've used check lists. I've used Mind Maps. I've organized tasks around geographic locations, subjects, sites, people, and straight lists--sometimes changing how the tasks are organized within weeks. And then changing them again," he relates. This diversity of tools and approaches can become necessary between different projects, but it can also be necessary on the same project as it evolves, he asserts.

"Moving 50 servers in a weekend transformed into moving 150 servers in a weekend. Migrating 100 PC's a week transformed into 450 PC's in a week across three continents," Herrick says of projects he's worked on in the past. "None of those situations allow your task management system to stay the same. You have to change, often on the fly, and needing to deal with a great amount of ambiguity in order to succeed."

There's a healthful reminder for busy entrepreneurs here. Sure, spend time reading up on the best ways to get more done. Of course, take time to consider ways to streamline your workflow. But don't take too much time because you might become wedded to whatever you decide on, and you'll most definitely serve your business better if you're willing to change and adapt along with the circumstances. Task (and time) management is very much a moving target.

How often do you change your approach to task management?