I heard another etailer mention this before at a conference before and I totally ignored it. Then I realized this is what was happening to a few of our products.
We have a product which we sell at $120. We have two competitors who sell the exact same product for $100. The lead time for all of us from the time of PO to arrival is around 60-90 days.
I noticed last month both of our competitors were outselling us nearly 10:1 because of the price difference. By the end of June both sold out of their stock . We were then left as the only source for these items and we've nearly sold out at $120/ea. I've now become aware of a couple of other products doing the exact same thing.
Of course, in an ideal world we would all always have sufficient stock but in reality this is rarely the case.
Long story short, it seems sometimes being the lowest priced guy doesn't pay.