Everytime this topic comes up on sports radio, someone always says something like, "Whatever they do, they can't have another Doyle Alexander for John Smoltz trade. Smoltz is a Hall of Famer and Alexander was out of the majors three years later." They always miss the point. Alexander was never intended to be a long-term guy. He was intended to get the Tigers into the postseason in 1987, and he did, going 9-0 down the stretch. Making the playoffs is very, very difficult, and if you have the chance you have to strike. (And it's not like Smoltz single-handedly would have kept the Tigers afloat during their lost decade. He probably would have bolted as a free agent first chance he got.)
People are using this argument against Derek Lowe now. If he can put them over the top, they've got to try. Prospects are hit or miss. A playoff opportunity won't be there every year. Minnesota's not going to start out in last place every season. Fans are too gunshy. Standing pat with all your prospects and never rolling the dice can turn you into the Pirates.