First, the impact of foggy days. Judging from the news photos of Kobe's plane crash, there is foggy weather at the crash site, but the fog in the mountains will be heavier. In this case, helicopter flight is inherently difficult, so this should be the main reason for Kobe's helicopter crash. There are many wrong judgments when driving in foggy days. The humid air in foggy days also has a direct impact on the performance of helicopters, which is why pilots fly so low.
Second, the altitude in the local mountainous area is unstable. The altitude of California where Kobe crashed ranged from 2,000 feet to 4,000 feet, and it kept fluctuating. In foggy days, the visual visibility of driving is affected. In the news, Kobe Bryant's helicopter suddenly rose from 1200 feet to 2000 feet. I believe this is also the reason. If you don't pull it up, you'll hit a mountain.
Third, the pilot is not familiar with the terrain. Kobe's helicopter is rented, of course, they are good at understanding the route, but Kobe's place is a mountainous area, and they may not be able to understand the terrain of the area. Just like we hire a driver with F 1 and then ask them to help us open a Sichuan-Tibet line in foggy days, even a skilled driver has to be timid first, so it is normal to make a wrong prediction in foggy days.
Therefore, the height is not a pot collision, but the terrain and weather, especially the unfamiliar terrain and bad weather, which is the most important reason.