Too expensive (initial cost to purchase CCR)
Too expensive (consumables to dive ie cells, sorb, O2 etc)
Training (Don't want more training or training is expensive)
Do not think they are safe
Too complicated (prefer simplicity of OC)
My buddies or team all dive OC
I don't understand enough about rebreathers
I have never tried one
I dive exclusively sidemount and don't want anything on my back
I only do short or shallow dives
I don't see a benefit
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