Whether at the trade deadline or during the offseason, teams are looking to improve throughout the year in MLB. Generally, the trade in mind is simple for a team, whether it's trading a star for prospects, trading hitting for pitching, or whatever is needed.
The same goes for the draft, though teams generally draft less for need and more by how scouts feel about a player. Based on scout knowledge, teams can get lucky finding a player late, and one of the prospects added in a trade can end up being a superstar.
Here is the luckiest acquisition for each team in MLB history, whether it's a prospect who became a Hall of Famer, or whether they drafted a guy as a favor to a friend, leading to the team acquiring the same.