The Wall Street Journal reports that Americans are now upgrading smartphones less. This is largely thanks to installment-based payment plans. It turns out, people don't like to pay for their phone every single month. There is also less reason to upgrade when new phones don't offer as many compelling improvements. The market hid behind subsidies for so long that people didn't realize how expensive phones can be. Americans got used to paying $200 up front for a new phone, now many carriers allow you to pay off the full $600+ price over several months.