I'm an immigrant to Android from iOS.
On my iPhone, whenever there is an incoming call that I didn't answer, or a new message, there is always a very visible notification on the phone desktop, so I can deal with it immediately. This doesn't seem to be happening with my Nexus 5. Sometimes I don't discover the message, which was obviously designed for immediate reading, until days after, when I am going through my messages.
I'm sure there must be a way to make the phone let me know, but I haven't figured it out yet.
On my iPhone, whenever there is an incoming call that I didn't answer, or a new message, there is always a very visible notification on the phone desktop, so I can deal with it immediately. This doesn't seem to be happening with my Nexus 5. Sometimes I don't discover the message, which was obviously designed for immediate reading, until days after, when I am going through my messages.
I'm sure there must be a way to make the phone let me know, but I haven't figured it out yet.