A deadline is a time by when something needs to be finished. An ocean of deadlines is a lot of deadlines. To have drowned in an ocean of deadlines is a metaphor which means that you failed to finish all of the tasks in time.

As a general rule, no. Most WikiReviewers projects are not assigned deadlines.

When project deadlines are not met, it is important to communicate with the team to identify the reasons for the failure. It is also important to come up with new guidelines and deadlines.

When I failed to meet with deadlines at that time I embarrassed to disclose but it was my first job and first assignment. From that I learned much experience and this has improved my ability to deliver. Then I understood the deadlines embarrassment and then onwards I have never missed any deadlines.

Yes there are deadlines for filing complaints. They are called Statutes of Limitations and they vary by jurisdiction.