Without its founding members’ comprehensive integration in a meaningful economic, political, and/or security sense, growing to include other states can be seen as little more than signaling to foreign partners with the presumed intent of attracting investment into their group. That’s not to say that the East African Community shouldn’t expand, but just that doing so before there’s a solid basis can lead to their well-intended efforts remaining ephemeral at best and at risk of paralysis, collapse, and even reversal at worst.
Mozambique interestingly, isn't part of this bloc...