Barry Boehm: Developing

“Economic principles underlie the overall structure of the software lifecycle, and its primary refinements of prototyping, incremental development, and advancemanship. The primary economic driver of the life-cycle structure is the significantly increasing cost of making a software change or fixing a software problem, as a function of the phase in which the change or fix is made.”

Barry Boehm

Source: Software engineering economics. (1984), p. 4

Life , Problem , Change

“Agile development methodologies promise higher customer satisfaction, lower defect rates, faster development times and a solution to rapidly changing requirements. Plan-driven approaches promise predictability, stability, and high assurance. However, both approaches have shortcomings that, if left unaddressed, can lead to project failure. The challenge is to balance the two approaches to take advantage of their strengths and compensate for their weaknesses.”

Barry Boehm

Barry Boehm and Richard Turner. " Observations on balancing discipline and agility http://people.cs.aau.dk/~jeremy/SOE2011/resources/Boehm.pdf." Agile Development Conference, 2003. ADC 2003. Proceedings of the. IEEE, 2003.

Failure , Change , Time

“The Code-and-Fix Model. The basic model used in the earliest days of software development contained two steps:
:1. Write some code.
:2. Fix the problems in the code.
Thus, the order of the steps was to do some coding first and to think about the requirements, design, test, and maintenance later. This model has three primary difficulties: (a) After a number of fixes, the code became so poorly structured that subsequent fixes were very expensive. This underscored the need for a design phase prior to coding. (b) Frequently, even well designed software was such a poor match to users' needs that it was either rejected outright or expensively redevelopment…”

Barry Boehm

Source: A spiral model of software development and enhancement. (1988), p. 61-62

Problem , Thinking

“Poor management can increase software costs more rapidly than any other factor. Particularly on large projects, each of the following mismanagement actions has often been responsible for doubling software development costs.”

Barry Boehm

Barry Boehm (1981) as cited in: Tyson Gill (2002) Planning Smarter: Creating Blueprint-Quality Software Specifications. p. 14

“If a project has not achieved a system architecture, including its rationale, the project should not proceed to full-scale system development. Specifying the architecture as a deliverable enables its use throughout the development and maintenance process.”

Barry Boehm

Barry Boehm (1995); quoted in: L. Bass, P. Clements, and R. Kazman (1998) Software Architecture in Practice, Addison Wesley Longman. Chapter 2

“Success in all types of organization depends increasingly on the development of customized software solutions, yet more than half of software projects now in the works will exceed both their schedules and their budgets by more than 50%.”

Barry Boehm

Abstract.
Software Cost Estimation with Cocomo II with Cdrom (2000)

Success , Dependency

“The stagewise and waterfall models. As early as 1956, experience on large software systems such as the Semi-Automated Ground Environment (SAGE) had led to the recognition of these problems and to the development of a stagewise model to address them.”

Barry Boehm

Source: A spiral model of software development and enhancement. (1988), p. 63

Problem

“What we see in both software development and military operations is a tendency for the pendulum to swing back and forth between extremes. Yet in most cases, we need a balance between armor and discipline and between mobility and agility. Actually, though, I would say that the leaders in both the agile and plan-driven camps occupy various places in the responsible middle. It’s only the over-enthusiastic followers who overinterpret “discipline” and “agility” to unhealthy degrees.”

Barry Boehm

Tom DeMarco and Barry Boehm. " The agile methods fray http://cf.agilealliance.org/articles/system/article/file/872/file.pdf." Computer 35.6 (2002): 90-92.