Tbh, I'm mostly watching anime from the start, but I didn't know some series starts from the manga. Therefore, I don't read manga as that much as I expected. Recently, I've started reading some manga (I forgot the names xp) and I must say they're more interesting than Anime.
It doesn't necessary mean Anime are superior than the Manga. Take Attack of Titan for example, since the manga is updated first and far ahead than the anime. It shows that the Manga has its own advantages. Attack of Titan is going to have its 2nd season in 2015.
I like both anime and manga and they have their own flaws. Therefore, if I love the anime series, then I would read the manga and see the story ahead (like Attack of Titan, Haikyuu!!, etc).