Ever taken a big long drink of a carton of milk that had already expired?  I have.  Twice!  After a long day on the consulting trail, I stopped into a convenience store to pick up a carton of milk and a snack pack of Oreos.  So far so good, only when I got to my room and opened up the milk…it was sour.  Arggggh!  Bad enough that the milk was bad, it was too much work to drive back over to the store and get a new carton!

Ever taken a big long drink of an assumption that’s already expired?  You know the kind.  You’ve got a few of them in your organization and at one time they were true.  Now?  Not so much.  But nobody’s ever really examined why the program is in decline and having to be propped up by everyone with excuses.


In When Growth Stalls, a really helpful article over at HBR, authors Olson, Van Bever, and Verry share some powerful ideas about how to examine your assumptions.  Here are two keys:

  • Leaders must bring the underlying assumptions that drive company strategy into line with the changes in the external environment.
  • Assumptions that a team has held the longest or the most deeply are the most likely to be its undoing.

So you know what I did the next time I went to the convenience store to buy a carton of milk?  That’s right.  I took out my glasses and read the expiration date before I took it to the counter.

Think you might need to take a look at the expiration date on your assumptions?

Assumption Expiration Dates