Canva is a great, free tool for graphic design. It's especially good for beginner-level designers, because it has such an easy-to-understand interface.
But, all software also has its limitations. Here are a few things you should consider:
No local file storage: Canva does not offer local file storage, which means you cannot access or change your files if the website is down or you have an issue with internet connectivity.
No source file: Unlike graphic design tools like Photoshop, you cannot export your Canva design as a raw file to make advanced edits. You'll need to make all edits on the Canva platform.
Not all assets are free: While Canva offers many free options, some images, fonts, and templates within the platform require payment.
Design overuse: Since Canva has millions of users, you may find that your favorite template has been used many times around the internet. This means you'll need to get creative to help your designs stand out.
Legal technicalities: While the media on Canva can be used for free or commercial and noncommercial use, you cannot use any of their designs (free or paid) within a company logo, and those designs cannot be trademarked.
Limited mobile support: Canva does have a mobile app, but it does not offer the same features as the website, mac, or desktop version. Keep this in mind if you plan to do a lot of design from your phone.