Haml

Raised as a usability problem by 5 people on Hacker News over 5 years (2009–2013), in 4 threads.

People raised many different problems with Haml, but no single problem has yet been raised by 3 people in 3 different months and threads.

Unreviewed issues were grouped by machine: Claude Haiku labelled each comment as a usability complaint, named what it's about and summed up the problem in a line, and a small model grouped similar problems. Nobody has checked them by hand. Expect mistakes.

The newest 5 complaints

Nesting elements is hard, and one-lining makes templates hard to read and maintain2013-02-19
Cryptic syntax forces rereading documentation when returning to a project2011-12-01
Whitespace formatting bites the user from time to time2011-11-30
Too much syntax for writing compared to Markdown, too little compared to HTML2010-11-16
Constant fighting with the syntax, and deep nesting becomes painful to write2009-01-20