Thursday, March 6, 2014

Need to estimate

Before going any further, I would like to mention that Neil Killick has written an excellent post related to this same topic: People Need Estimates. You might want to read that post before or after my post, which tells one story where estimates were "needed".

We need estimates


Prioritization in our project was initially made by dividing the features into four categories: must, should, could, and won't have. Our team had basically finished all the must haves and since there was time left before the pre-defined launch date, the management wanted to prioritize the should haves.

The should have items had already been prioritized based on business value and the request for the team was very clear: the management needs estimates for all of the should have items so that they can make the final prioritization.

Or perhaps something else?


I already revealed above what the management actually needed. They needed to decide how the development team should spend the scarce time there is left before the launch. They didn't need estimates. Surely estimates is one solution for this problem, a very typical one actually.

So what's wrong with the estimates related solution? One thing is that if you don't estimate the value, estimating the cost is quite debatable. Another thing is that in this case the should have list was very long. If the management wanted the team to estimate the whole list, it would have meant that we spend several days on trying to understand what some of the items mean and how we should implement them. Or we could have just thrown the famous "educated guesses" without even knowing what we were supposed to build.

Input for management


I didn't like either of the approaches so we did something else. We had all the items on our whiteboard vertically placed in the initial priority order. We went through the list and placed each item horizontally in one of the three columns: simple, complicated or external dependencies, and very unclear or lot of uncertainty. This took about an hour of our time.

When we presented the revised list for the management, our message was the following:
  • The items in the simple column are such that you could move them up in the priorities if you like since they should be rather straightforward to implement.
  • The items in the complicated column contain more risk and you may want to drop their priority if you like.
  • If there are some really important items in the very unclear column, we should investigate them more so that we can understand them better. (But we shouldn't investigate all of them because that would really waste our valuable and scarce time.)
Besides that we told them that if they really need some numeric values, we can use our statistics about the development lead times. They weren't interested in the numbers, the table was just fine.

Decisions made


Probably the most interesting thing happened (or did not happen) after we had presented the table: our categories did not really have an effect on priorities. The items that were initially on the top had so clear business value so that they remained on the top although they were mainly complicated ones. The simple items did not get to the top even though there were - well, simple. And the management asked us to spend time on only one very unclear item.

This tells me the message that the estimates were initially asked basically just because that's how it has always been done. On the other hand, it tells me another message too. Our management (intuitively perhaps) understands that it shouldn't focus too much on the short-term development cost but rather on the long-term business value. This is something I really like.

3 comments:

  1. nice example, short term absorption unlikey needs estimates from the same team that did the development.

    Now it's start date minus 30, would an estimate - to some level of confidence - for the all in cost of the project before it starts, provide management with some data for decision making around resource allocation?

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