Why does apple release a new iphone every year?

I don't think it's fair. We all spend so much on a new iphone and find out a new one s coming out next year… It just really annoys me!

Because Apple are in the business of making money and a lot of their customers are vain enough to think they always need the latest model.

Because it makes them money and gets them a lot of attention from all the news outlets that treat every Apple product launch as if it where a news story. Also it is not like lasts years smartphone is useless when a new one comes out. Sometimes the latest isn't as good as the one before like when Galaxy S6 didn't have a removable battery nor an expandable memory.
There are people like us who keep putting off replacing a smartphone for that reason unless switching phone companies or phone brakes and people who buy the lates version of every product Apple sells.

That's how Apple generates huge profits. Although, as the market saturates, fewer and fewer people are buying new iPhones. The only ones who buy them every six months are geeks and fashionistas.

Well if you don't like that then you'd hate Samsung, because of their creeping up release dates their flagship phones are sometimes 2x a year. That's ignoring the fact they release the phone & then months after in some cases release a new phone based on that other one with better specs.

As far as Apple though
1. No one is forcing you to get the latest iPhone
2. Its easier to do these days with the major carriers & Apple offering trade-in/every iPhone plans to get the new ones annually.

I buy them every 2 years.

After recent expose of Iphone security by FBI, Apple now wants to release Iphone with new updates every year so that they keep their Iphone security level high and who know's this is the part of their new marketing strategy.