Neighborly competition
Many races compete for runners on the same date. Their distances, locations, and amenities may vary, but they still worry about losing runners to the "other" event.
Two such races take place practically next door to each other in Chicago IL.
The Ravenswood Run 5k, a CARA Circuit event produced by Fleet Feet Sports, saw turnout of its fast-growing event almost double last year to 2,421 finishers on the city's north side.
The Lakefront 10-miler, a CARA Registered race, produced by Universal Sole, attracted 1,211 finishers (down from its peak four years ago) on the north side lakefront, less than three miles away.
Despite the competitive feelings of the race organizers, both races are viable, they've both won support of local running groups, and their combined promotion probably attracts more attention.
Another event near yours on the same day may not be ideal, but if you offer something unique, the competition may not matter.