I recently went to HostGator as my provider with a VPS Level 5 account. My site is 6 years old and they looked at all the usage, traffic, memory etc before suggesting VPS Level 4 and I went to 5 just in case.
At the start my site was slow and crashed all the time. I was asked to take all plugins out and put them back one at a time which I did. For 2 weeks it was fine and nothing happened. Now it's slow and crashing again. I was told "Your scripts need to be optimized." I said, "What does that mean?" And they said that is all they can say. They say it's taking 100 percent of memory. I said how? and they said we don't know, it's your site.
So, what does that mean? I had a website developer who did not seem to understand WordPress but his work was finished long before this happened and the site is not that complex.
Thank you for any help.