- Requirements that change mid-stream, dozens, sometimes hundreds of times - Team has to do speculative development for ill-formed or understood problem domain

- Requirements that change mid-stream, dozens, sometimes hundreds of times - Team has to do speculative development for ill-formed or understood problem domain - Requirements that are improperly gathered - Requirements that are underspecified - Poorly understood problem in general - Fighting bugs in system libraries - Fighting bugs in third party libraries - Fighting issues with integration on deployment and/or third party anything - Complex underlying technology requiring its own kind of discovery (like in the OP) - Poor/incorrect documentation - Project members that go off on their own, refuse to communicate, deviate wildly from the project style, break things - Management that insists on doing things from scratch - Management that insists on using buggy, broken, etc. 3rd-party or even in-house systems/libraries for political or faux-business reasons - Constant software developer interruptions - Long meetings that consist of circular discussions, politics, back-and-forth arguments about personal preferences disguised as "important project stuff" - Administrative minutiae that never stops adding up - People leave a project partway through, taking project knowledge with them - Broken/buggy tools/environments/systems - People getting pulled off a project to work on another project - Bad use of project management, source code management, other tools - Insistence on wheel reinvention for well-understood problems for career advancement, resume building, or boredom-relief purposes - Low morale / poor focus due to bad management, co-workers, bad tools, bad work environment - Low morale / poor focus due to reliance on: late night work (leading to insufficient sleep), weekend work, little/no time off or breaks, reliance on crunch/death marches - Dealing with company/project politics in general - Lack of focus due to team member resume-polishing/interviewing part way through a bad project - Occasional project sabotage