When teams don't need strong estimates, then Kanban works well.

When teams do need strong estimates, then the best way I know is doing a project management ROPE estimate, which uses multiple perspectives to improve the planning.

https://github.com/SixArm/project-management-rope-estimate

R = Realistic estimate. This is based on work being typical, reasonable, plausible, and usual.

O = Optimistic estimate. This is based on work turning out to be notably easy, or fast, or lucky.

P = Pessimistic estimate. This is based on work turning out to be notably hard, or slow, or unlucky.

E = Equilibristic estimate. This is based on success as 50% likely such as for critical chains and simulations.

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Marsymars a day ago | parent | next [-]

> E = Equilibristic estimate. This is based on success as 50% likely such as for critical chains and simulations.

I've found giving probabalistic estimates to be hopeless to effectively communicate, even if you assume the possible outcomes are normally distributed, which they aren't.

	▲	jph 5 hours ago \| parent [-]
		Critical chain planning has a purpose for the 50%. It's not perfect-- but it's better than other ways, in my experience. Wikipedia: "The justification for using the 50% estimates is that half of the tasks will finish early and half will finish late, so that the variance over the course of the project should be zero... Because task duration has been planned at the 50% probability duration, there is pressure on resources to complete critical chain tasks as quickly as possible, overcoming student's syndrome and Parkinson's Law."

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swatcoder a day ago | parent | prev | next [-]

Three-point or PERT estimates are in the same vein, but are just an old and established business process concept and not a trademarked "project" from a (defunct?) consultancy.

https://en.wikipedia.org/wiki/Three-point_estimation

https://projectmanagementacademy.net/resources/blog/a-three-...

And yeah, they can be useful when you can must put numbers to things and can decompose the work into familiar enough tasks that your estimation points are informed and plausible. Unfortunately, in a field often chasing originality/innovation, with tools that turn over far too often, that can be a near-impossible criteria to meet.

	▲	jph 5 hours ago \| parent [-]
		Yes you're correct. PERT 3-point was my starting point and I wanted to add a critical chain 50% estimate. BTW the SixArm name and ROPE is merely my personal work. Way back when, I had to put on the trademark because someone else said my work was theirs.

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torginus a day ago | parent | prev | next [-]

This sounds like that if you don't trust a fortune teller, you can mitigate it by going to 4 different fortune tellers, and then somehow combining their predictions into your much more certain future.

	▲	jph 5 hours ago \| parent [-]
		Yes except in practice it's worked out more like this... Realistic is favored by tech teams. Optimistic is favored by salespeople and marketers. Pessimistic is favored by lawyers and compliance people. Equilibristic is favored by project managers and military. Each stakeholder gets the kind of fortune they want. The important aspect (to me) is that the four viewpoints show all the stakeholders that their viewpoints are quite different.

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TheOccasionalWr a day ago | parent | prev [-]

So now you have 4 wrong estimates to work with :) To have some predictability you should have small features. That's the only thing that can give you strong estimates. No industry has solved giving strong and correct estimates - it's in the name, it's estimation!

	▲	jph 5 hours ago \| parent [-]
		Yes small features help enormously. I've used ROPE and work breakdown structures (WBS) to estimate multiple projects at thousands of staff hours to under 4% of actual. The ROPE advantage is that it uses multiple perspectives, which gets stakeholders understanding that the estimates are imperfect and depend on many factors.