Triggering was originally designed for repeating waveforms, well before storage scopes were a thing. Triggering basically means a positive or negative transiti

Triggering was originally designed for repeating waveforms, well before storage scopes were a thing. Triggering basically means a positive or negative transition over/under a certain level. You can set the level manually, and this gives you a basic left/right (phase) shift on the display. It's really not a bad UI if you understand what it's trying to do. Often you want to see what happens after some reference point or - literally - some triggering event like a pulse. Constant sampling doesn't solve the problem. You still need to work out where the point of interest is. That's fairly simple for a static repeating waveform, but not at all a trivial problem for any waveform that changes over time - as many audio waveforms do.