It shouldn't, and in Sweden it obviously isn't – I think it's great! But the moment you start doing things slightly out of this norm, maybe you rent out your apartment for some time, maybe you have capital gains, maybe you were paid dividend as a small business owner... it gets complex real fast.
Skatteverket is a pretty knowledgeable organization though, and quite friendly when you have questions to ask so I recommend giving them a call if you need things clarified. They've helped me out a lot simply by educating me when I've called asking all sorts of dumb questions.
As much as I dislike paying taxes, the process of doing so is anything but inconvenient in Sweden.
1. Sign-in from Bank-id at Skatteverket
2. Review pre-populated amounts
3. Digitally sign acceptance filing with Bank-id
If I just have one salary from one employer all year round, why should it be more complicated than this?