Maximizers hold that the absence of any attainable good is, as such, bad, and that a life that lacks such a good is therefore lacking. I disagree. One central reason for my disagreement stems from the moral psychological import of regretting the absence or lack of any and every attainable good. This regret is a central characterizing feature of narcissistic, grandiose, and other defective selves. It is also characteristic of those who are too hard on themselves, who are too driven and too perfectionistic.
This doesn't strike me as a good (truth-indicative) reason to disagree with the Maximizer. It may be bad, or even in a sense inappropriate ("defective"), to regret every little regrettable thing. But those things may be regrettable all the same.
How is this? Of course, it isn't news that rationally justified or warranted attitudes may be undesirable ("bad") in some circumstances. But one may find more puzzling the suggestion that warranted attitudes could characterize a kind of psychological defect. After all, aren't warranted attitudes precisely those that it would be (rationally) appropriate or fitting to have?
Well, sort of. But -- given that our minds are only finite -- we need to distinguish (i) the appropriate answer to a question, from (ii) whether a well-functioning agent would raise that question in the first place. To actively regret something requires first attending to it. So it may be the active attention, rather than the resulting regret per se, that is defective.
To illustrate: imagine that Bob is constantly regretting the slave labour that went into building the Great Pyramids. His obsessive historical sympathy interferes with the living of his life, to the point that he ends up absent-mindedly stepping in front of traffic and losing his legs to an oncoming vehicle. Years later, Bob's wife Sally just can't stop regretting that Bob lost his legs. Every time she looks at her husband, she sees his disability (and little else).
Clearly, Bob and Sally are defective moral agents. But nobody would conclude from this that slave labour and traffic accidents aren't really regrettable. Rather, the problem is that (like the immodest person whose achievements and status are excessively salient to his mind) they are attending to the wrong things. Likewise, I suggest, with Stocker's perfectionist. If it would have been better for us to do Y rather than X yesterday, then that's the correct answer to the question what we should have done. In this sense, our doing X instead was indeed regrettable. But that doesn't mean we should now regret it, because it may be that we shouldn't be raising that question at all. (Spilt milk, and all that.) This is perfectly compatible with the Maximizer's claims, for Maximization is a view about correct answers, not correct questions. (One might extend it to the latter by raising the question of "what question to raise next"; but obviously the answer to this needn't be "whatever question Maximizing Consequentialism has an answer for!")