Story Points in Agile for Defects

Story Points for Defects

I have been working with several teams on implementing TFS as they want to follow ALM.  Currently they are doing velocity and burn up charts in a spreadsheet.  I noticed that they were assigning story points to defects.  They were doing so to help with planning as a certain percentage of the teams time is dedicated to fixing defects reported by the customer.  I started thinking about if that was the right way to go about it.

If story points are the measure of value delivered to the business or customer then defects should have a negative impact on the value.   A piece of working software with no defects has a perceived value of non-working software (defects).   Therefore fixing the defects later should be 0 story points since that “value” was already delivered to the customer in a previous release.
 Teams with better quality will have a higher velocity and teams that spend more time fixing bugs will have a lower velocity.  This may portray a more accurate picture when planning work and releases.

Your thoughts?

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