[thejteam]

Perhaps the self-interest in this case is "managing expectations".

If they tell everybody to prepare for a 20 percent drop but the market falls 10 percent, then everybody feels good about themselves and Blackrock.

If they tell people to expect flat markets but instead get the same 10 percent drop, then people panic. They withdraw their money. Move to a new broker. Because obviously Blackrock wasn't prepared for this. Or stuff it in a mattress. Because obviously something unexpectedly bad is happening.