Everyone gave really good reasons!
What I love about manga is its variety: there's something for everyone including those who are either cynical and/or have never read manga before. Since there are tons of stories being published each year, I'm sure there's at least one title that will appeal to someone. If you want romance, there's romance. (Is the setting in high school or a workplace?) If you want action, there's action. (Do the characters have special powers or do they achieve certain feats with physical strength alone?)
This goes for comics as well, but I'm always impressed by how intricate stories could be told through pictures and speech bubbles. Unlike novels where the author can manipulate words to hide and show something through metaphors, manga has to be careful and think outside the box if they want to incorporate literary techniques such as foreshadowing. If they show too little, the readers won't get it later on, but it will be too obvious if they show too much.
I also have huge respect for mangaka since it's not an easy thing to do to make this occupation a living. They have to go through the stress of trying to get serialized, facing rejection, cancellation, meeting deadlines, etc. I've seen several timetables of mangaka (albeit only weekly ones), and apart from food, sleep and bathing, they virtually have no "off" time. Virtually every single day and hour consists of work.
