The lottery is the NBA’s silliest event. High-ranking team personnel travel across the country to sit on stage as the results are announced. They don’t even watch the actual drawing (though others do that). They just sit and grin or grimace for the cameras based on how ping-pong balls bounced in another room earlier in the night.

The silliest part: How darn important it is.

Dynasties are built in the lottery. Rebuilds are upended in the lottery. Jobs are saved and lost in the lottery.

Few lotteries have been as important as this year’s. The future of the NBA’s competitive balance could swing tonight, and highly touted Zion Williamson is only the start of the significance.

The big three reasons this lottery is particularly critical:

Prospect tiers

Zion Williamson is the quality of prospect who comes along only once every few years. He’s huge, athletic and skilled. Few college players, especially freshmen, have ever affected the game like he did at Duke.

WHOOSH!

That was the steep drop to Murray State point guard Ja Morant, who’s nearing consensus as the No. 2 prospect. Then there’s another drop to Duke forward R.J. Barrett, probably the probably the popular pick as No. 3 prospect. Then, there’s yet another drop to whomever you fancy as the fourth-best prospect in this draft.

These divisions between tiers aren’t solidified. There’s still time for movement as players work out and interview.

But, as it stacks up now, the reward for getting the No. 1 pick is far greater than the reward for getting the No. 2 pick, which is far greater than the reward for getting the No. 3 pick, which is far greater than landing somewhere in the middle of the lottery. Those clear delineations only add to the stakes tonight.

Protected picks

The drama doesn’t end with the high picks. A few trades involving protected picks will have major ramifications.

The Grizzlies owe the Celtics a first-round pick, which is top-eight-protected this year. Neither team wants a middling lottery pick in this weak-looking draft. If not moving into the top four, Memphis would rather convey its selection this year. Boston would rather wait, as the protections drop in subsequent years. The Grizzlies have a 26% chance of getting a top-four pick and a 31% chance they get the undesired No. 8 pick. So, that leaves the Celtics with a 43% chance of getting a pick in the 9-12 range.