AH:
Sunfish,
Quite right, I apologise. Not being able to retract the gear is obviously a scary incident for all involved, including the passengers who thought they 'were going to die' and worthy of an article in the newspaper and a story on the evening news every time it happens!
It still appears you don't understand what you are talking about. To put it simply, the "failure to retract" may be a symptom of another safety related problem - anything from a tire or wheel failure to fire. We are also assuming here that the gear remained "down and locked". If you have ever watched a LAME approaching an aircraft and gingerly putting a locking pin into a suspect gear after a cockpit warning and return, it's possible you might understand.