In golf, pace of play matters. It's in the Rules of Golf, but the language is a little vague.
Under Rule 6-7 of the Rules of Golf:
The player must play without undue delay and in accordance with any pace of play guidelines that the Committee may establish. Between completion of a hole and playing from the next teeing ground, the player must not unduly delay play.
There are no particular time standards set out in the Rules, which intentionally leaves those standards to tournament committees and presenting authorities. Not every tournament is the same, so prescribing a pace of play for every conceivable event under the sun makes no sense.
That's where the PGA Tour, as well other professional golf tours, come in and specify a pace-of-play policy for tournaments under their control. They decide how long a player has to take a shot and in which situations a player will be timed to make sure they're complying with the expected pace.
On the PGA Tour, their pace of play policy starts with an assumption that the player will abide by what's called time par, which is a course-by-course determination of how long a twosome or threesome should take to play each of 18 holes and a full round in total. The enforcement of the pace of play policy starts when a group is determined to be "out of position." That happens to the first group of a round -- on any starting tee box -- when they exceed the allotted time par. Subsequent groups are considered out of position when they exceed that allotted time per hole or reach an open par 3, or they reach an open par 4 or par 5 and haven't yet played a shot.
It's at that point that a rules official can put a group on the clock after informing them of the decision. It's at that point, all players in the group will be timed on each shot until they get back up to pace. In addition to group timing, a PGA Tour rules official can, at their discretion, begin timing individual players for any reason, even if the player's group is not out of position.
Generally speaking, players are afforded 40 seconds to play a stroke. They're allowed 60 seconds to play a stroke if they're the first to play on a par 3, first to play a second shot into a par 4 or par 5, first to play a third shot into a par 5, or the first to play around or on the putting green.
If a player exceeds the time allotted on any stroke, they're then informed by an official. For the first offense while being timed, they're given a warning. If they get another bad time while under watch in a single round, they get a one-stroke penalty. If they get a third bad time, they're given a two-stroke penalty. If they get a fourth bad time, they're disqualified. At the end of a round, bad times are forgotten for the purposes of penalty strokes.
However, players can earn fines for accumulating bad times over the course of a season. The first bad time during a season does not lead to a fine. The second bad time leads to a fine of $5,000. For every bad time after that, the fine is $10,000 per offense. Bad times in any PGA Tour event count.
There are also fines for being timed in the first place. The first nine times during a season that a player is in an out of position group that is being timed, the player is not fined. On the 10th time a player is in an out of position group and timed, they're fined $20,000. After that, each subsequent offense is a $5,000 fine.
If a player is fined for either reason, both sets of fines double the next year, and they can double each consecutive year a player is subject to a fine under the policy.