During the community summit at DrupalCon Prague 2013 - a group of people worked on further developing a complaints and conflict resolution policy and process. During that workshop we brainstormed around the nature of conflict - and identified two different kinds of conflicts we needed to address. Technical, Practical, and Drupal specific issues and Human nature, communication type issues. Here's the list:

Technical issues Human nature
Modules / Issues
D.O processes
e.g. : Module Review Queue for people that do not understand why it takes so long

e.g.: Answers from people that are not well received or lack respect

Reputation
e.g.: Some tasks are quickly resolved if you know a person that knows a person.

Business Competition / Eco System
e.g.: People that move to other Drupal Companies but keep encountering their previous employers in the community.

e.g.: Working together in the community but hard competition in the work environment if the companies are from the same local community.

Contribution
knowledge stream : How to contribute and how to spread this skill
e.g. : There is a lot of process but which one should one use and why does one need to read so much.

e.g.: Lack of information can be frustrating, such as unwritten rules.

Forking
e.g.: Forking a module because there is someone that is not happy how process works and finds it easier to fork the module. There could be different reasons why.

Systemic Issues
e.g.: The U.S. Government has a law that they have to archive everything that happens in the name of the U.S. Government.

For this reason they have a user on Drupal.org that is named after the organisation.

Now, the policy forbids organisation user names and enforces every account to be a person. This is a deadlock as law and policy are collisioning.

Not acknowledging or Valuing all contribs equally
e.g.: Documentation edits are not always commits
e.g.: Translation edits that happen outside of drupal.org
e.g. Drupalcamp talks, etc…

“I know best”
Issue queues
IRC
e.g.: Comments and/or replies that assume the other side knows about his or her ability to not explaining him or herself anymore.

Language and culture
Due to the barriers of the language it could be that certain bits are misunderstood and were taken as offensive. Written words do not come with additional hand-gestures so it could be meant in a very different way.

Assumptions
Assuming that some people have the knowledge while they have not and depicting them on that.
e.g.: Commenting heavily on certain contribution while it was intended as a help to improve solving a certain use-case. This is demotivational and could cause conflict and build up frustration.

General Agendas (Interest, political, business wise, focus, ...)
Companies have agendas depending on the direction certain companies head to.
e.g.: A company focussed on migration will have more interest in migration modules and to fix them. They will probably have a direction they want to take that might not map with the author of a certain migration module. Person vs Company is a source of possible conflicts.

False sense of hierarchy.
e.g.: Not daring to contact “higher-up” people due to the fear that they are “too busy” or would not respond anyway.

Harassment and Bullying
Sexual comments, balance, people that feel threatened. Severe problems in such a diverse community.
e.g.: A twitter rant or a personal attack due to natures one can not do anything about.

Territorial issues
Geography & authorship
Drupal groups in the same area but they are competing. Group names that were pre-occupied by people that have nothing to do with that area and convince them to “hand-it over”

Whining in general
Commenting without constructive wording is useless

“Bad Day” factor
Sometimes someone just has a bad day and due to the digital nature it is not always clear.

Empathy and/or interpersonal skills
Not everyone is equally skilled to word their feelings into English text or are able to feel empathic and or related to one another. This should be noted and taken into account. Conflict could be avoided if this is recognized.