Final answer:
It is often true that the product description will be used as the meta description if a custom SEO description is not provided, dependent on the CMS or e-commerce platform.
Step-by-step explanation:
If a custom SEO description is not given for a product, the default behavior can vary depending on the content management system (CMS) or e-commerce platform in use. However, it is common for systems to use the product description as a fallback for the meta description. This means that, in many cases, the statement is true. The meta description is a brief summary of a web page's content that search engines may show in search results, helping users understand what the page is about before they click. It's important to note that while this is a common practice, ideally, a custom SEO description should be specifically crafted to optimize for keywords and user engagement.