In this writeup I am exclusively refering to the meaning of the word "diving" in association football (soccer). So, dear yanks and disappointed deep sea afficiandos, please don't tune out, because I will not only explain the different kinds of reasons for diving, I will also elaborate on the consequences.
So yeah, in association football, diving is the art of pretending the opponent has committed a foul in order to gain an advantage (the possible advantages are listed in the next section). Typically, the diving player is in possession of the ball and has one or several opposing players next to them. Instead of trying to get past the opponents through the use of elusive properties such as skill and technical or tactical ability, the player "takes a dive" by falling to the ground and possibly, although not necessarily, feigning injury. Physical contact with the opponent may occur before and during the fall, but not significantly enough to constitute an actual foul - in fact, the diver typically seeks or even initiates contact to make the fall appear more realistic.
Motivations of Divers
Reasons for diving may include (roughly in order from not-so-noble to extremely unsportsmanlike):
1. protecting yourself from a foul, or an exceptionally rough tackle: This is sometimes used as an excuse for diving, but the reasoning is clear. In soccer, players are not protected well from harsh tackles that may result in injury, and bad fouls can have players on the receiving end spend an entire year in rehabilitation, or end their careers in the worst case. In order to prevent that from happening, a player might decide to "take off" by himself just before significant contact with the opponent occurs.
2. preventing loss of possession: This is the most simple reason for diving. You don't want the other team to get the ball plain and simple, and you don't want to lose a duel with another player. So if it looks like you are about to lose the ball, a dive can be a means to simply keep possession.
3. getting a little break (late in the match): The number of substitutes is very limited in soccer and with extra time, matches can last for over two hours, while modern football tactics require players to be moving constantly. If a player is very tired, diving can be a way of causing a short interruption and catching some breath. This case isn't mentioned very often, but it occurs.
4. playing for time (late in the match): If a team is satisfied with the current score and the match is getting closer to its end, players may start diving as a means to kill time through a lot of interruptions - remember, the clock does not stop in soccer, although the referee takes interruptions into account when deciding how much extra time to award.
5. preventing a counter attack: This is basically the same situation as (2.), but with a more specific context. Soccer is a dynamic sport and one goal can easily decide a match. Therefore, in a situation where losing the ball would be very dangerous, a player might dive in order to prevent what is called a "fast break" in basketball - given that they are about to lose the ball and the team is looking vulnerable to a quick counter attack.
6. earning a good free kick opportunity: This is perhaps the most common reason for a dive. Note that in the cases cited above, a free kick is also awarded (as long as the referee "falls" for the dive), but that's a meaningless advantage if the position on the field is not good enough. When a player tries to primarily earn the free kick, they are typically in a good position for an attempt at a goal, if only the opposing players weren't there! So, in order to take a shot with no annoying opponents around, the player dives to earn a free kick. The diver might also try to win the free kick if they are a bad finisher, and want somebody else on the team to have a shot, because anyone on the team is allowed to take the free kick.
7. getting the other team cautioned: If the dive is well done, it will look like a serious foul was committed by the opposing player, and it is likely that they will get a yellow card for this. The yellow card is just a warning, but it will have the opposing player be more cautious with their tacklings to prevent getting sent off the field for repeated foul play. Especially if this player is a defender, this caution can seriously weaken their team's play.
8. earning a penalty: The ultimate prize for diving is the penalty. In professional soccer, penalties have about an 80% conversion rate and are sometimes seen as "guaranteed goal". Penalties are only awarded if a foul by the defending team occurs in the penalty area, and a dive in this area is naturally the most lucrative.
9. getting one of the opposing players sent off: A red card and the concurring dismissal from the match is the highest punishment a referee can hand out, and therefore it's also the most vile possible reasoning for taking a dive. However, this is a very speculative motivation, except in some specific situations as detailed below. Lacking such a specific situation, the chance of a red card can rather be seen as a "bonus" chance added to the other motivations for diving. Divers are faking it anyway, so they might as well make the supposedly committed foul seem as spectacular as possible. Since the referees are used to theatrics, whether a foul has actually occurred or not, they will generally only send off a player if the offense was obvious, but red cards have been handed out for victims of divers nonetheless.
Now, to the specific situations in which a dive can more easily cause a red card: The rules of association football state that a player committing a foul may also receive a red card if the foul is the only way of preventing a clear chance at a goal (even if the foul by itself is not card-worthy). So if the attacking player decides to take a dive instead of taking the shot, the opposing team may easily end up with one player less on the field. Because they are renouncing a great chance at a goal and because they also need to speculate on the card, this "option" is not popular even among known divers. That is, unless the chance occurs in the penalty area, in which case the diver might both get one of the opposing players sent off, and earn a penalty on top of that. This is especially unsportsmanlike and can easily be described as vile because you are per definition missing out on a great opportunity to score a goal just to hurt the other team as a whole, and one innocent player in particular.
Often, the reasoning behind a dive will consist of a combination of these motivations, although reporters typically single out the diver's deep desire for a free kick (or, if close to the goal, a penalty) as the only reason.
Short Term and Long Term Consequences
Up until this day, the percentage of diving attempts that gets punished with a yellow card is very low. In some high-profile cases divers have been banned for two or three matches post-match, but this is even more rare. The worst case for the diver typically is that the referee does not react at all; that the match simply goes on and they lose the ball. Because of these extremely negligible consequences, the incentive to dive can be very high from a short term perspective.
Note however that, no matter whether their dives are successful, players performing them regularly or in high profile matches may experience serious mid- and long term drawbacks. Their reputation will sink, and that has consequences on the field. Especially in the higher leagues and in international football, the referees are often familiar with the teams and will inform themselves about players with a "diver" reputation before a match. Therefore, when a player with such a reputation actually gets fouled, the referees are less likely to see the foul. In turn, and beyond that, it's statistically proven that known divers will get fouled more often because opposing teams know that the referee will be less likely to punish them.
Last but not least, divers will also always have to take the fans into account. Players performing dives in high stakes situations may get hostile reactions not just from the opposing fans, but even their own fans might end up booing them, sometimes until the player ends up leaving the club, and beyond that.
Iron Noder Challenge 2017