Argentine can hardly contribute anything to BRICS, instead it would have been a needy partner in it. While the optics would be good for BRICS if Argentine join, but BRICS don't lose anything when Argentine cancel the membership. Life goes on. Frankly BRICS should focus on attracting Indonesia to join, that would be a big win. I know Indonesia is already considering to join, though they back out at the last minute for unknown reason, but there is still interest in Indonesia to join. BRICS should also focus on attracting Cental Asia countries to join. That would help a lot if BRICS want to establish BRICS currency