Considering a connection mode depends on the data exchange requirements. If you are using applications e.g erp or any other which is not based on http/s, or simply stating that if you are using any server on premises and applications which are pretty old then you might face connectivity issues. Further if your business needs more than average security on the network, and if you use a wireless network, then you might need to employ or outsource the security part. This might be expensive. To summarise, if you have aged apps running with data on premises and if you need more than average security, then wired with a domain envirónment would do. Contrary to this, if you are having your data on cloud say office360 and an erp which works on hosted enviorment, a wireless environment would be sufficient.