Complex sentence: Other phenomena, such as groupthink, can also be going on at the same time, for real-world accidents of course usually have multiple causes, and not just the single cause that could have prevented the accident at the very last minute.
Split into simpler sentences: Other phenomena, such as groupthink, can also be going on at the same time. Real-world accidents of course usually have multiple causes, and not just the single cause that could have prevented the accident at the very last minute.