It's not idle. The base idle rate is about 5 times worse than what you get when holding down left click, and it's upgraded individually for each ball you get, which means the newest ball you have (which will likely represent the bulk of your income, being the highest base value ball and thus most cost efficient to upgrade the value of) will have it's auto rate at or slightly below that once-every-five-seconds value.

Not interested in playing a game where my income plummets that drastically if I'm not willing to sit there and hold left click...seemingly for my entire playtime, given that I can never afford to meaningfully upgrade the auto drop time on any of the balls that actually meaningfully contribute to my income, so I dropped it. Finger was getting a bit tired of having to constantly hold the mouse button down, honestly, wasn't worth it to me.

But, you might be able to enjoy this if you have a sturdier finger than me and don't mind having to constantly hold down left click for...who knows how long. Maybe it becomes idle after long enough, but I played enough to know it would take long enough to leave my finger sore, joint pain is a bitch. And I didn't feel like waiting half an hour before coming back to actually make any progress, so. 2 stars, because it could be worse. I can see a version of this I'd enjoy, but it ain't here right now.