I've never liked that phrase because I think it sells teams short by devaluing its members.
Successful teamwork requires collaboration, which means putting team success ahead of your own agenda.
But a key measure of team success is throughput. Efficient throughput depends on effective leadership and each team member doing his or her job efficiently, reliably, accurately and on time.
So, there may not be a small 'i' in team but there is a big 'I'. As in, 'Don't worry, guys, I have it covered.'