Definitions
There are 2 meanings of the phrase
Blind Alley.
Blind Alley - as a noun
(figurative) a course of action that is unproductive and offers no hope of improvement
Example: "All the clues led the police into blind alleys"
Example Sentences
"We walked down a blind alley and had to turn back."
"The investigation reached a blind alley, and no further progress was made."
"I feel like my career has hit a blind alley; I don't know what to do next."
"The company invested a lot of money into a project that turned out to be a blind alley."
"He followed the directions but ended up in a blind alley."