The global smartphone market has stopped growing, and Apple has only once out-performed the market.
For iPhone 8 to be regarded as a success, Apple must do something it has only ever done once before: Grow its sales faster than the market as a whole and take market share from other companies.
Historically, Apple's phones have only ever sold to about 15% of all users globally. They are expensive, and Apple has creamed off the high-end users and the profits that go with them.
That has not been a problem — until the last year or so. When the market was growing Apple got 15% of that growth and grew with the market. Now, however, the market has stopped growing. Everyone who wants a phone now has one. So Apple has a different sales problem in front of it than the one it is used to.
These charts illustrate how Apple is boxed-in at a price-point in the market that may make iPhone 8 look like a failure.
Apple has kept the average selling price (ASP) of iPhone between $600 and $700. But in the market as a whole, the average price is now under $300 and falling. The rumour is that the new iPhone might cost more than $1,000.
None of this would be a problem if Apple could grow iPhone sales. But recently, the "installed base" of users is hardly growing, according to Deutsche Bank.
And now the global market for phones as a whole has stopped growing.
For iPhone 8 to be regarded as a success, it must actually add new iPhone sales — something Apple hasn't meaningfully done since 2015.