According to the Aberdeen Group, a one second delay in page-load time equals 11% fewer page views, a 16% decrease in customer satisfaction, and 7% loss in conversions.
According to the UK: Internet Statistics Compendium which includes Data from Rackspace, 38% of UK online shoppers abandon websites or apps that take more than 10 seconds to load.
Speed is a metric used by Google to rank search results, Google considers a page to be ‘slow’ if it takes longer than 1.5 seconds to load.
74% of users will leave after waiting five seconds for a mobile site to load.
Another interesting fact, Most blogs using WordPress are hosted on shared hosting plans.
Shared hosting simply means that many websites are hosted on a single web server, and that the server’s resources (CPU and RAM) are shared among every customer account on the machine.
Shared hosting plans are pretty cheap but this does not mean they are not good. The major word that causes problems for shared hosting users is the word “Unlimited“.
Most WordPress installs are hosted on shared hosting plans and majority of these installs are by people new to blogging.
Hosting companies mislead customers with the “unlimited” tag that are placed on Shared Hosting plans. Unlimited data transfer bandwidth, unlimited website storage, unlimited emails and unlimited domains.
The truth is Shared hosting is the most limited hosting plan available on the web. Once you know this, you know just enough to enjoy a shared hosting plan.
The most common cause of site crashes on shared hosting plans are plugins.
Every plugin you activate makes WordPress a little slower. Some plugins are highly resource-intensive and do not play well with shared hosting.
Here is the list of Popular WordPress Plugins to Avoid if You in Shared Hosting
1. Broken Link Checker
2. Google XML Sitemap
3. Yet Another Related Posts Plugin
5. WordPress Popular Posts
In here you can find the reasons and alternative.