As it is technically very easy to set up an issue tracker these days, it often happens that teams set up their own issue trackers to handle their own issues and tasks. It happens for many other types of tools, such as editors, but editors are among the personal tools of a developer, and their primary use case isn't the sharing of collaboration surfaces with other people. Issue tracker proliferation is therefore a problem, while editor proliferation isn't.
A contributing cause of the issue tracker proliferation problem is that a large organization might standardize a type of tracker that few actually like to use. A typical reason is that only the needs of one type of team, such as the quality assurance team or the operations team, is being considered while deciding on an issue tracker. Another reason is that only a limited amount...