Reflective inconsistency refers to a disagreement between your earlier self and your later self about what your earlier self should have done given only your earlier state of knowledge. It can informally be called regret or remorse.
More precisely, if you do Y, and later you think "Knowing only what I knew before doing Y should have deterred me from doing Y,", then you are reflectively inconsistent.
Tuesday Self: <spends 5 dollars on a chance to win 6 dollars if a fair coin flip lands heads>
Wednesday Self: "That wasn't worth the risk, and I should have known better."
Tuesday Self: <spends 5 dollars on a chance to win 6 dollars if a fair coin flip lands heads>
Wednesday Self: "That was lucky, but it wasn't worth the risk and I should have known better.>
Non-example:
Tuesday Self: <spends 5 dollars on a chance to win 6 dollars if a fair coin flip lands heads>
Wednesday Self: "I would have been better off not taking the bet, since the coin was going to land tails.>