Business
The all about agile blog has compiled a list of why IT projects fail:
Project Initiation & Planning Issues
- Unclear or unconvincing business case
- Insufficient or non-existent approval process
- Poor definition of project scope and objectives
- Insufficient time or money given to project
- Lack of business ownership and accountability
- Insufficient and/or over-optimistic planning
- Poor estimating
- Long or unrealistic timescales; forcing project end dates despite best estimates
- Lack of thoroughness and diligence in the project startup phases
Technical & Requirements Issues
- Lack of user involvement (resulting in expectation issues)
- Product owner unclear or consistently not available
- Scope creep; lack of adequate change control
- Poor or no requirements definition; incomplete or changing requirements
- Wrong or inappropriate technology choices
- Unfamiliar or changing technologies; lack of required technical skills
- Integration problems during implementation
- Poor or insufficient testing before go-live
- Lack of QA for key deliverables
- Long and unpredictable bug fixing phase at end of project
Stakeholder Management & Team Issues
- Insufficient attention to stakeholders and their needs; failure to manage expectations
- Lack of senior management/executive support; project sponsors not 100% committed to the objectives; lack understanding of the project and not actively involved
- Inadequate visibility of project status
- Denial adopted in preference to hard truths
- People not dedicated to project; trying to balance too many different priorities
- Project team members lack experience and do not have the required skills
- Team lacks authority or decision making ability
- Poor collaboration, communication and teamwork
Project Management Issues
- No project management best practices
- Weak ongoing management; inadequately trained or inexperienced project managers
- Inadequate tracking and reporting; not reviewing progress regularly or diligently enough
- Ineffective time and cost management
- Lack of leadership and/or communication skills
Note that these points are all about management, rather than technology.
Projects fail when expectations are not aligned with results; in a sense, that's the definition of failure. Given the complexity of IT projects, with many moving parts distributed among a diverse group of stakeholders, it's not surprising that expectation mismatches occur all the time.
Differences in expectations, goals, and priorities are substantial contributers to non-technical complexity, which is the underlying cause of most IT failures.