Project Scheduling Problems

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Project Scheduling Problems
Paul Sorenson Department of Computing
Science University of Alberta
CMPUT 401 Software Engineering
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What is a Schedule?

• That part of the plan that deals with -
  milestones - deliverables - resources
• Success of project is often judged on how
  well you stay to the schedule as opposed to
  how well you are executing the plan.

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Bad Schedules

• Microsoft Word for Windows 1.0
• 5 years to develop, 660 person-months, 249 KLOC

Report Estimated Estimated Actual
Days Relative Date Ship Date Days
to Ship to Ship Error
Sep-84 Sep-85 365
1887 81 Jun-85
Jul-86 395 1664
76 Jan-86 Nov-86
304 1400
78 Jun-86 May-87 334
1245
73 .. Jun-89 Sep-89
92 153
40 Jul-89 Oct-89 92
123 25 Aug-89
Nov-89 92
92 0
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Causes of Overly Optimistic Schedules

• external, immovable deadline (Y2K, Christmas,
  tax time)
• managers only accept best case estimate
• deliberately underestimated to get a winning
  bid
• interesting project and developers want to do it
  even if under-funded
• workers are more effective if under the gun a
  little
• project is simply poorly estimated
• managers/developers want a challenge

• project begins realistically but new features
  are piled on and before long the schedule
  becomes overly optimistic

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Beating Schedule Pressure

• McConnell says you cant solve a problem using
  Rapid Development until you know how to handle
  schedule pressure

schedule pressure
More
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Beating Schedule Pressure

• Three factors that make up bulk of problems
  associated with optimistic schedules

• Wishful thinking
• Ignorance
• Poor negotiation skills

Principled Negotiation - separate the people from
the problems - focus on interests, not
positions - invent options of mutual benefit -
insist on using objective criteria
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Inventing Options for Mutual Gain
Product Options

• move some desired functionality to the next
  version
• deliver the product in stages (e.g, ver 0.7,
  0.8, 0.9, 1.0)
• cut features altogether
• polish some features less
• relax detailed requirements for some features
  until later

Project Resources

• add more developers, if its early in the
  schedule
• add higher-output developers (e.g., subject-area
  experts)
• add more testers
• add more admin support (e.g., project
  documentation tracking)
• improve developer support environment (e.g.,
  offices, coke machine)
• increase level of end-user involvement and
  executive commitment

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Inventing Options for Mutual Gain
Project Schedule Options

• set a schedule goal but no an ultimate project
  deadline until product design is done (or at
  least requirements defn.)
• if its early in the project, agree to reduce
  development time as you refine product
  specifications and design
• agree to use estimation ranges and to refine
  these as the project progresses

Politically Charged Options (to be used only if
you know who you are negotiating with)

• provide exceptional support so developers can
  focus more easily on development task -
  shopping service, catered meals, limo
• provide increased motivational perks - paid
  overtime, all expense paid trip to Hawaii,
  profit sharing