Qatar was the first islamic country which has hosted the FIFA world cup - the next in line is Saudia Arabia
They are rich states and they want to prove to the world that they have potential and they can host the big event so well
Saudi Arabia is trying really hard to win hosting rights to the 2030 FIFA World Cup. And that is one of the reasons why they spent so much money to bring Cristiano Ronaldo to the Saudi Professional League. And I have a more positive opinion about Saudi Arabia when compared to Qatar. They are a country of close to 30 million people and a lot of sports facilities exist there already (unlike the case with Qatar). Also, the new King has shown a lot of tolerance to modern lifestyle, unlike the case with some of the neighboring monarchies such as Kuwait and Qatar.