User Experience Research on Random Quote Machine

How Long Would It Take You to figure out how to use my random quote machine??

So, I just finished my Random Quote Machine, and I started to wonder how many students think about the usability of their projects. Maybe this kind of UI questions are for web designers really since those projects are targeted for us to practice algorithm scripting. But I know a lot of web developers do design works themselves at small companies. Please let me know if this isn’t true.

anyway I have a tendency to build my project based on very minimal designs.
Such as this one: Project Link -
And I was wondering how long would it take you to figure out how to use my random quote machine.

The thing is I got rid of an obvious action button (saying next quote) )and instructions(saying something like: Click here for random quotes). Does the lack of such element makes my site harder to navigate?..
Here is my last project with similar looks and probably same problem?