It’s every IT professional’s worst nightmare to have a project fail like the healthcare.gov site did, and as we wake up screaming, we’re tempted to believe proper estimation will save us from similar fiascoes. Johanna Rothman doesn't believe this is the case. She believes estimation wastes valuable time that could be spent working, and it won’t ensure success anyway.
If you are having similar misgivings about the estimation process, it may be time to ask yourself why you are still doing it. An alternate solution would be to cut your work down into much smaller, more manageable chunks. The larger the project, the greater the chance your estimation will be wrong. If you turn the large project into a list of much smaller projects, you eliminate the need for estimation entirely.
Prioritize which small tasks need to be done first. Then let these smaller projects progress in a natural flow. If you absolutely feel the need to estimate, try order-of-magnitude estimation. This should take you a couple hours instead of a couple days. The time saved can be used to deliver the project even faster, and to rest nightmare-free between tasks.