My interpretation of it is that a sunset is something that is beautiful. But when you see one starting you know it means it's ending soon.
So, perhaps, this is about having strong feelings for someone, knowing that it'll never work out but going for it anyway. I'm sure many people have been in the situation where they have this immediate strong connection with someone but it burns out as quickly as it lit up and they foresaw exactly where it was going before it even began.
My interpretation of it is that a sunset is something that is beautiful. But when you see one starting you know it means it's ending soon. So, perhaps, this is about having strong feelings for someone, knowing that it'll never work out but going for it anyway. I'm sure many people have been in the situation where they have this immediate strong connection with someone but it burns out as quickly as it lit up and they foresaw exactly where it was going before it even began.