If you have the money, you can hire people that are extremely specialized in specific areas, for example you may have a team of 5 people that is specialized on

If you have the money, you can hire people that are extremely specialized in specific areas, for example you may have a team of 5 people that is specialized on constantly analyzing and optimizing landing pages, or another one that studies only app usage in the first 3 hours after install, etc. These are not generally teams you would want assemble for a startup, but people who have years of expertise in very specific fields tend to be better at it than generalists for obvious reasons. You can do successful mobile apps wth 3 people, but if you can afford it and if politics/bureaucracy doesn't get much in the way, it can be worthwhile to have a larger team of specialists.