Bolting has occurred in my current lettuce crop, this means that the plant has flowered before producing a lot of leaf, the plants are a lot smaller and don't yield as well but let's just say our next lettuce crop is on the way when the seeds knock off early.
In terms of cannabis, this can actually be advantageous for us during a Spring crop, we wish to get them to flower prematurely in order to get a crop in before the June solstice, since the flowers are what we're after (usually not the raw leaf), we can obtain small harvests of high quality early on in summer because of bolting as seen with some of my Blackberry plants