Some industries are dependent on one supplier for critical materials.  For example, all Major League Baseball teams (and their feeder teams) rely on just one supplier for the mud they rub on all the baseballs.  The MLB uses about 240,000 baseballs every season, and each one is prepared for the game by manually rubbing them with mud from the Delaware River.  This is required.  But, there's only one mud supplier, and he gets it from a secret location on the Delaware River.

Why is this mud important, if not essential?  In the vast catacombs of baseball lore, certain essential features reign supreme.  The size and dimensions of the infield are sacrosanct.  The distance of the pitcher from the batter is unchallenged.  As to the baseball, its size, stitching, the leather cover, and inner core must meet rigorous standards (well, more or less).  Rawlings is the current supplier of baseballs to the major leagues.  These new, smooth-coated spheres gleam in the pitcher's hand.  And that is the problem: the pitcher's whole purpose is to strike out the opposing batter.  He must use torque, e.g., spin on the ball to deceive the batter causing him to swing and miss the ball.  The new, gleaming projectile may be too smooth and slippery to firmly control.  Applying a thin sheen of mud to the new baseball before it arrives in the pitcher's hand is, and has been seen by generations of baseball experts as the answer.  The game, in the view of many pitchers and teams over the generations depend on it.  And the MLB may itself depend on it.

.       MLB leans on longtime mud supplier, not Rawlings, to coat balls
.       https://www.si.com/mlb/2019/08/07/baseball-mud-rawlings

What happens if (when) the mud supply dries up?

The discussion topic is about the MLB and other industries who are dependent on sole-source suppliers.  Have there been any disasters because of sole-source suppliers, and how do companies mitigate this situation?