Stock outs equal sales lost... that may never be gotten back.
Needing a gift for a business acquaintance this morning, I stopped by a local Starbucks to pick up a gift card only to be told they had run out -- "come back in two days when they might be in".
Undeterred, I proceeded to a second Starbucks and found that they too were out. Upon being asked how this could happen to multiple stores, a worker stated that there was a delay in getting the new Fall themed gift cards. The worker then suggested buying one at a local Walmart or grocery store (they might not have run out of the old style).
The end result today? A local competitor to Starbucks sold a $20 gift card. That does not sound like much because it isn't... but add that to how many other gift cards sales were lost due to this multi-day stock out snafu and Starbucks might be out a decent amount of sales.
In any event, although a minor consumer matter, it was not very impressive marketing effort by Starbucks.