One user starts editing a wiki article and needs one hour.
A 2nd user starts editing the same article at the same time.
-> there is no warning message or sth like that
Both user make massive changes to the article.
At the moment one user decides to save the article, the message pops up:
"This page was edited by "User1" on "DATE/TIME". Saving the page will overwrite those edits."
-> so one edition of the article is always lost.
So a lock mechanism would be great. Or at least a message, that someone is working on the Wiki at the same time