Why is launching Sitebuilder takes so long?

For the past few weeks, launching Sitebuilder is extremely slow. It takes approximately 10 times longer to launch Sitebuilder. I have two accounts and the same problem occurs on both. Have you changed something in the process?

It looks as it it loads a lot of files everytime. Even if I shut down Sitebuilder and restart it immediately after, it takes as long to load. What is the problem?