The NBA draft lottery is an annual event held by the National Basketball Association (NBA), in which the teams who had missed the playoffs the previous year participate in a lottery process to determine the draft order in the NBA draft. The NBA Draft lottery started in 1985. In the NBA draft, the teams obtain the rights to amateur U.S. college basketball players and other eligible players, including international players. The lottery winner would get the first selection in the draft. A lottery pick denotes a draft pick whose position is determined through the lottery, while a non-playoff team involved in the process is often called a lottery team.
Under the current rules, only the top four picks are decided by the lottery, and are chosen from the 14 teams that do not make the playoffs. The team with the worst record, or the team that holds the draft rights of the team with the worst record, has the best chance to obtain a higher draft pick. After the top four positions are selected (from the lottery slotting system), the remainder of the first-round draft order is in inverse order of the win–loss record for the remaining teams, or the teams who originally held the rights if they were traded. The lottery does not determine the draft order in the subsequent rounds of the draft.
Since the 2019 draft, the NBA changed the lottery odds (the bottom three teams will all have an equal 14% chance of winning the top pick) and increased the number of teams selected in the lottery from three to four.
History
1947–1965: Territorial picks
In the earlier drafts, the teams would draft in reverse order of their win–loss record. However, a special territorial-pick rule allowed a team to draft a player from its local area. If a team decided to use its territorial pick, it forfeited its first-round pick in the draft.
1966–1984: Coin flip
In 1966, the NBA revamped its draft system, and introduced a coin flip between the worst teams in each conference to determine who would obtain the first overall draft pick. The team who lost the coin flip would get the second pick, and the rest of the first-round picks were determined in reverse order of each team's win–loss record.
While the coin flip system gave the worst teams in each conference an equal chance to have the first draft pick, but had a disadvantage in that if the two worst teams overall were in the same conference, the second-worst team overall would have no chance of obtaining the first draft pick.
1985–1989: Early lottery system
After the 1984 coin flip, which was won by the Houston Rockets, the NBA introduced the lottery system to counter the accusations that the Rockets and several other teams were deliberately losing their regular season games in order to secure the worst record and consequently the chance to obtain the first pick. The lottery system involved a random drawing of an envelope from a hopper. Inside each of the envelopes was the name of a non-playoff team. The team whose envelope was drawn first would get the first pick. The process was then repeated until the rest of the lottery picks were determined. In this system, each non-playoff team had an equal chance to obtain the first pick. The rest of the first-round picks were determined in reverse order of the win–loss record.
Starting from 1987, the NBA modified the lottery system so that only the first three picks were determined by the lottery. After the three envelopes were drawn, the remaining non-playoff teams would select in reverse order of their win–loss record. This meant that the team with the worst record could receive no worse than the fourth selection, and the second-worst team could pick no lower than fifth, and so on.
The New York Knicks were the first winner of the lottery in 1985. They selected Georgetown University standout Patrick Ewing with their first overall pick. However, speculation arose that the NBA had rigged the lottery so that the Knicks would be assured to get the first pick. Even though the envelope system was highly criticized, it was used until 1989 before being replaced by the weighted lottery system in 1990.
Since 1990: Weighted lottery system
In 1990, the NBA changed the format of the lottery to give the team with the worst record the best chance of landing the first pick. The worst non-playoff team that season would have 11 chances, out of 66, to obtain the first pick. The second worst would have 10 chances, and so on. Similarly to the previous system, the weighted lottery system was also used only to determine the first three picks, while the rest of the teams selected in reverse order of their win–loss records.