Not if you are a responsible adult, it doesn't. Ask the U.S. Army. They did a study and showed no effect. If this were true, why would many Eastern cultures, and Jamaicans, use marijuana to help them work harder? `Amotivational syndrome' started as a media myth based on the racial stereotype of a lazy Mexican borracho. The prohibitionists claimed that marijuana made people worthless and sluggish. Since then, however, it has been scientifically researched, and a symptom resembling amotivational syndrome has actually been found. However, it only occurs in adolescent teenagers -- adults are not affected.
When a person reaches adolescence, their willingness to work usually increases, but this does not happen for teenagers using marijuana regularly -- even just on the weekends. The actual studies involved monkeys, not humans, and the results are not verified, but older studies which tried to show `amotivational syndrome' usually only suceeded when they studied adolescents. Adults are not effected.
The symptoms are not permanent, and motivation returns to normal levels several months after marijuana smoking stops. However, a small number of people may be unusually sensitive to this effect. One of the monkeys in the experiment was severely amotivated and did not recover. Doctors will need to study this more before they know why.
What you think, from personal experiences?.
From being a smoker during my teen years i couldnt blame weed for being unproductive. I just aint care enough.