A certificate you can show a customer does not mean you will get the job, not in a million or billion or trillion years.
It is about professionalism, selling skills, marketing, good equipment for the job, etc.... not a piece of paper.
There are certified hacks out there in every industry, worst is HVAC. I know guys that make a living on just fixing what other HVAC companies' damage because even though the guy has a certificate and license, does not mean he was properly trained on the job for certain situations. There are bad electricians (have license and certificates), bad plumbers (have license and certificate), bad doctors (many years of college, medical school, license and certificates) but sometimes people get hurt, wrong operation or die from them.
If your customer is picking someone else, you need to find out why, is it price only, is it professionalism, is it selling skills, is it because they were referred highly? Sometimes they will tell you, sometimes they don't want to tell you why and blame it on the spouse.