Let's say hypothetically that you have the following:
Looking at 5 years worth of data, we have in one group:
$200 Avg. Order Value 1 Purchase Frequency (1 lifetime purchase)
Using the lifespan for all customers, they average 0.5 years.
So when we look at the 1-time purchasers, and apply:
AOV * PF * Lifespan
LTV = $200 * 1.0 * 0.5 = $100
How would it make sense to someone that the LTV for a 1 time purchaser is less than their average order value?