Why shouldn’t I use the manufacturer’s product descriptions in my online shop?
Using descriptions supplied by the manufacturer on your website is common but not recommended because it duplicates content from elsewhere on the web. Other sellers supplied by that manufacturer will also have the same descriptions, so it becomes a battle of who ranks the highest. The rest will simply not be shown on Google. Google dislikes duplicate content and detects and shows only one version of it where it can, so this practise should be avoided.