It is true that money does not guarantee goals, and building a great team is not easy, but that is the decision they have taken, while Bayer Leverkusen are just trying to take advantage of their opportunities to improve their financial condition.
Currently, the Bayer Leverkusen coaching chair is in the hands of Erik Ten Hag, I am quite curious who the first recruit they will bring to Leverkusen. And at the end of this season, the club that ETH used to coach, namely Manchester United, plans to sell its players. And the question is, will ETH bring in the players he once recruited for Man United and bring them to Leverkusen..?
You are right that simply spending much of money does not guarantee great team building one takes more than just cash and it sounds like you believe Leverkusen is more focused on smart financial growth. Big news is that Erik ten Hag is now coaching Bayer Leverkusen which makes everyone wonder who he will sign first. Since his old club Manchester United is selling players this summer it is very likely he might try to bring some of those familiar faces to Leverkusen. He knows what these players can do they understand his tactics and they might be cheaper or easier to get which would help them fit into his new team faster.
I don't think that new Bayern Leverkusen coach Eric Ten Hag will consider signing any player from Manchester United because most of those players contributed to Ten Hag's misfortune when he was coaching the club, why will him sign any of them now that he has become Bayern Leverkusen new boss. ETH understands the situation of Manchester United and since Xabi Alonso has developed a good number of players at Bayern Leverkusen, it will be a disappointment to add players that cannot match the energy of the already existing players and Eric Ten Hag should be careful not to ruin the legacy of Xabi Alonso at Bayern Leverkusen before his departure to Real Madrid. Manchester United players cannot be suitable for ETH at Bayern Leverkusen, he rather sort for players elsewhere.