To make money with a website you need traffic because without website traffic or anyone visiting your website you're unable to make money.
The amount of website traffic you need to earn money will depend on how much money you want to make with your website.
If you want to earn $10.00 per day you'll need less traffic than you would need to earn $100.00 per day with your website.
For $10.00 per day you're likely to need 2,000 daily unique visitors. And if you want to earn $100.00 per day you will likely need 5,000 to 15,000 daily unique's depending on the niche your website is in and how high the CPC is from the Adsense or other ads.
Of course if you're selling your own product or service you could earn $100.00 per day with less visitors. It just depends on how you're making the money through your website and what topic your website is about.