Why is it so hard for the rich and powerful to apologize? Because the corporate apology is no ordinary apology. Upset your customers badly enough, and they'll demand not just a mea culpa, but some kind of restitution. Which can get awfully expensive.
So executives are loath to say anything that implies legal responsibility, and taking responsibility for one's actions is, well, the key to a real apology. "I deeply regret that the loss of life" is not the same as saying "I'm sorry that my company caused the deaths of 5,000." Tokyo Electric Power Company, facing a failing and dangerous nuclear power plant, was left issuing expressions of sympathy that only sound like apologies. Such as this from Tepco CEO Masataka Shimizu: "We believed we had built nuclear plants that could withstand natural disasters, but in the end this situation arose, and for that I am truly sorry."