Most websites rely on organic traffic for attracting new visitors. This means you’ll probably need to compete with hundreds if not thousands of other pages for the keywords your content targets. In other words, you need to be better than the competition if you want to climb to the top of relevant Search Engine Result Pages (SERPs).
A lot of people favor platforms such as Instagram over Pinterest, although the latter can be a fantastic source of traffic – particularly for image-heavy sites. However, without a verified website, people can share your content without others knowing where it came from.
WordPress, as a platform, is more secure than many others. However, there are always vulnerabilities in any service you use. The more popular a platform is, the more likely that people are going to try and crack its defenses.