I come from a country that has a huge weed culture so I'm not really against it. Many people say that weed is not addictive and that may be true but there are some bad things about it too. What I don't like is that is becomes "habitual". Habitual in the sense that instead of doing productive things in your free time that you turn to smoking weed. This means that you'd likely be more successful if you'd have spent the time doing something productive than smoking weed.
It's just my opinion.
I agree. It has the best effect if you are tired and kinda "deserve" it. Otherwise, as everything else in life, it can have a negative effect if it becomes a day-to-day all-day activity.