Even having your own in-house IT team does not make you fully independent.
In this instance, an in-house IT department would be about providing first-level and second-level support within your company. This would involve you employing IT staff who are able to solve the majority of your hardware and software problems themselves. However, your company will never be fully independent as you ultimately still rely on external providers for a number of services: your computer will be HP or Apple, your Windows operating system Microsoft, and you will have Adobe Photoshop. If these experience in-depth problems, you will need assistance from specialists working for these service providers. But you do have your own in-house specialists your employees can speak to first, who will ideally be able to solve most problems themselves and very efficiently.