The light output from a laser is effectively brighter than a LED or incandescent bulb because it’s coherent. This means that all of the photons being emitted have exactly the same wavelength, and the same phase (ie the peaks and troughs of the individual waves match up), and tend to all go in the same direction.
In a normal light source some of the waves will be interfering and cancelling each other out, and they will be spreading out more, so you get less effective brightness .
All of this is why you can shine a 5W LED in your face all day long, but I really recommend you don’t do the same with a 5W laser.
(That wiki article on coherence isn’t very helpful, I can have another crack at explaining it in layman’s terms if anyone’s interested)
