dual-curing adhesives can partially cure in seconds — the portion of the joint that's exposed via optically clear material cures in seconds, with this portion serving as a kind of "clamp" that helps the portion of the joint that's in a shadow to cure over a longer period of time
Preactivated light-curing adhesives can cure in ~20 seconds. "Preactivation" is similar to "activation on the flow". (TODO — what is this black magic called "preactivation"? I'm still trying to understand this bit.)
On manufacturing lines, various adjustments will be used to minimize curing time, such as curing inside an oven.