Checking out big projects can take 'forever'
(on slower or memory limited systems, such as certain Synology-brand Network Attached Storage systems, caused by 'calculating deltas')
Hard to 'retrofit' older versions in the version tree
(after committing newer version on beforehand)
Git is a great version control tool. It seems less suitable for less powerful CPUs however because computing time seems to grow exponentially. Furthermore, like with most version systems, it is hard to change history which could also make initial commits of existing (folder based) projects harder. It seems better if the user is in control about history policy and not the version system.