People insist on looking at this through their default prism of "closed source bad, open source good". But people with crypto experience have other prisms; for instance, "competent, well-vetted crypto" versus "amateur enthusiast crypto". Sometimes open source is also competent and well-vetted, but vetting is expensive, and there is a lot of amateur crypto out there.

> Sometimes open source is also competent and well-vetted, but vetting is expensive, and there is a lot of amateur crypto out there.

You seem to be implying that one must be a hobbyist in order to write incompetent crypto software with no or incompetent review and tend to need company resources to get quality code reviews.

Having crypto is often an important checkmark and tack on for shipping a product and usually no one in the product group is competent to analyze the security of the way they tacked on encryption. If a few in the larger company are competent, they will avoid reviewing these projects. Being the engineer everyone associates with delays and frustrations doesn't do much for you and there will never be any proof of the costs you may have prevented.

The few better than I know how to criticize implementations that I have seen haveusually had considerable cross company and university involvement. That usually means open source or a lot of NDA and complex license agreements for cross organization code sharing.

I have no idea what you're trying to say here, but just a random stab at responding: my perspective in this discussion comes from managing a consulting practice that, among a few other things, specializes in assessing the security of cryptographic implementations.

I've been in a role of evaluating security vulnerabilities on security products and features from many different origins..

All I am saying is that I am in a position to estimate ~9/10 of everything critically exceeds the competence of its authors to safely combine features and security. So a primary explanation for failure that only applies to 40%(60%?) of the market doesn't sound right to me.

So either we disagree considerably on proportion of software that is poorly implemented or you are saying the majority of commercial software is also written by hobbyists?