C3.ai is deeply unprofitable and will take years to emerge from that hole.C3.ai (AI -1.45%) has become a fairly popular stock due to the artificial intelligence (AI) investing trend. Because it's one of the few companies that is nearly a pure-play investment in AI, many investors have taken a look at it.However, if you're considering investing in C3.ai, I'd urge you to consider this one red flag, as it could save you from heartache in the future.C3.ai's growth is strong and is picking up speedAlthough growt ...