Danny has never really tanked. He has always gone for the win now and rebuild through other teams 1sts mentality. I mean, Danny has had what 7 lottery picks in his entire tenure. He traded up for Banks, drafted Smart with the C's own pick, traded the C's own pick for Ray Allen, drafted Brown, Tatum, and Langford with another team's pick, and traded another teams pick that became Sexton.
So during Ainge's entire tenure as a GM, his team has only been bad enough to draft in the lottery 2 times i.e. Smart and Jeff Green.