One reason is the difficulty of predicting when and where lightning will strike; tall structures do attract more lightning strikes, but it’s hard to move them into a storm’s path. Instead, researchers often use small rockets carrying a fine wire to trigger strikes, an approach [Electron Impressions] recently replicated (more details). The wire trailed by a rocket creates an artificial leader, ideally triggering a controlled strike. To consistently get a strike, the rocket needs to be launched under a strongly-negatively-charged region of the cloud. For a more reusable solution, some researchers have also experimented with using drones to trigger lightning.