Calibre One C-level interview questions

I interviewed for a retained search that Calibre One was conducting. The interview with the associate and then the Partner was fairly standard for a boutique exec search firm. That process was fine and professional as I'd expect. The Partner then set up interviews with his client. After I interviewed with their client, the Partner never followed up or responded to my emails. As a senior level exec who has been recruited and placed by larger and more reputable firms than Calibre One, I was disappointed to see such poor professionalism by this firm. While it was obvious that the client did not want to pursue my candidacy, which is normal, I expected Calibre One to follow up with a brief call to simply state that and provide any feedback - even an email would have been satisfactory. But to not respond to my follow-up emails lacks professionalism and respect that any size firm, but especially a small firm (compared to one of the big 5 Exec search firms), should exhibit. I will certainly think twice before entertaining an opportunity with Calibre One (as it wasn't the first time they have reached out to me) and will certainly share this poor experience with my network.