Name Hometown Program Employer/Student Fun Fact 1

Introduction The Requirements Problem (1)

Requirements Problem What is the goal of writing requirements ▫Quality Software ▫On time ▫At or under budget ▫Satisfied all of the users needs  And as many wants as possible Need to stay focused on the short and long term Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Software development process ▫Is comprised of several activities ▫All of which must work together This will accomplish the objectives otherwise you have wasted effort Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Developing software is like manufacturing ▫You have set times, locations, and people responsible for certain tasks ▫You should always provide a means for feedback and have error detection The most effect companies at manufacturing produce a product that best meets the consumers needs!! Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem SW Development is a highly customized product … ▫Two models  Develop per customer  Give enough options for all users ▫With obvious exceptions of shrink-wrapped COTS (Commercial Off-The-Shelf) Must find a way to effectively manufacture software that can be customized. Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Efficient manufacturing of a product includes: ▫Accurate specification of product ▫Efficient production process ▫Ability to quickly ID & remove defects Unlike most products, most SW defects can be repaired/fixed ▫Eliminates having to discard defective products ▫But can be very expensive to fix  Analysis  Development  QA  … Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem What are some of the issues that we face ▫Who are all the users? ▫Do the users know what they want? ▫What is the users budget? This presents a difficult scenario in that you need to establish the first two pieces before you can make a decision on what you can do with their budget Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem How do most projects fair ▫Not good!!!!  Study done in the 90s reports that in the US  $250 Billion/yr in application development  $2.3 million for a large company project  31% of projects are cost of $81 billion  53% of projects cost double or more than the original estimate Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Important questions the studies did not ask ▫Did the completed software meet the users needs?  Was anything cut to get the software done ▫What was the quality of the product?  QA tested?  Known Issues ▫Is it maintainable?  Feasibility of updates  Availability  Scalability w/ performance can be a big issue Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem So why do these projects fail? The most common factors are ▫13% Lack of user input  We do voice of the customer  Customer steering committees  Alpha and Beta releases  Voice of the business  What is a good direction from a business standpoint  Input from cross functional teams ▫Other business units ▫Other teams (QA, DEV) ▫12% Incomplete requirements and specs ▫12% Changes in requirements and specs All directly related to managing requirements All communication issues Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem So how can we make a project successful Communication!!! ▫Clear complete requirements ▫Executive and management support  Some projects will run over budget or need more resources ▫User involvement Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem ESPITI (1995) Study of SW problems ▫See fig 1-1 p. 8 (next slide) ▫2 largest problems  Requirement Specifications  Managing Requirements ▫Coding is rarely the major problem  It is usually the most expensive  They code what is designed Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Figure 1.1 Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Studies done by (3 boards suggest) ▫Keys to successful SW Development  Ongoing communication with the users  During requirements elicitation  Thorough documentation of requirements  User Validation of requirements  Maintenance of reqs as they change  Traceability of reqs throughout project to ensure they’re implemented ▫This requires a defined process that is followed Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem How do software defects originate? Capers Jones study (1994) on SW Defects ▫Reqs contribute most defects to delivered SW ▫Design defects come in a close second ▫56% of defects due to the above 2 reasons ▫Coding defects are common but also easier to fix Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Table 1-1 (Capers Jones Study) Copyright Leffingwell, Widrig, & SIS Faculty Defect OriginsDefect PotentialsRemoval Efficiency Delivered Defects Requirements1.0077%0.23 Design1.2585%0.19 Coding1.7595%.09 Documentation0.6080%0.12 Bad Fixes0.4070%0.12 Total5.0085%0.75

Requirements Problem Cost of fixing defects ▫Studies that show the costs of fixing errors  Cost progressively increases as the SW process continues  100 – fold increase in cost to fix the error in the Maintenance phase versus the Reqs. Phase  A requirement defect cascades into design coding, etc Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Figure 1-2 Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem Requirement defects can cause ▫Re-specification, redesign, recoding, retesting, … ▫Re-education of customers/users ▫Lost sales/Recognition of revenue ▫Refunding money ▫Product recalls ▫ Emergency patches/Hot fixes ▫Warranty Costs, Legal judgments Copyright Leffingwell, Widrig, & SIS Faculty

Requirements Problem So how are we doing now: ▫Not much better  Still about 30% of projects fail  ml ml  _papers/frese/ _papers/frese/ ▫This stresses the need for increased training!