"Shark Tank" host Mark Cuban isn't your average billionaire. In fact, Cuban says he communicates daily with everyday entrepreneurs who reach out to him.
"My email is pretty public, so I get pitches via email and I'll respond directly," Cuban said on the "Raising The Bar" podcast from couple Alli Webb, co-founder of Drybar, and leadership coach Adrian Koehler.
Cuban said he probably gets 750 to 1,000 emails a day from people pitching ideas. But catching his eye is the tricky part, he said. "Remember 90% are delete, delete, delete, glance and delete."
In fact, Cuban said it typically takes him about two seconds to decide whether respond to an email or to delete it.
"I'll read the first paragraph or two and if it is something that catches my attention, and is interesting and I think is forward-thinking, then I will just start peppering them with questions," Cuban said.
If the person is able to answer his questions and "teach" him something, he then turns it over to his team to do more due diligence. "I have different people with different types of expertise and I'll ask them to dig in and cover the bases that I'm not fully versed on," Cuban said.
Cuban said he typically dedicates two to three hours to going through email and "another couple hours" responding to emails.
Cuban, 62, who has an estimated net worth of $4.2 billion, according to Forbes, also provided some tips on grabbing his attention.
First, "just get right to the point" in the email, Cuban said. The "longer the backstory, the worse the deal."
Cuban doesn't want a long, drawn out story of how "you were in a motorcycle accident or how your fourth grade teacher didn't love you as much as she should have," he said. However, if there is something truly unique about you or something that differentiates you, point it out early, he said.
And no one should ever refer to their idea as "the next Uber" or "the next thing that is going to kill Covid-19," he said.
In particular, Cuban has seen thousands of pitches with subjects lines claiming to be the "best disinfectant for Covid-19" or "we're reinventing the mask." "Look, its great that people are making masks, but there are so many hustle deals. Hustling is great; I'm a grinder at heart. But not all these things are investable," he said on the podcast.
Finally, the "absolute worst thing," you can do is email Cuban every day, especially if you don't get a response. People often mistakenly think that repeated emails show "persistence," but not to Cuban. "I don't even want to tell them, but I just go into Gmail and set a filter for their name so it will auto delete it and we're done," he said.
That said, Cuban does encourage people to follow-up with him in a timely manner. "If you can come back and make the idea better, or you've learned something, it's not a bad thing to say, 'Ok, when I first emailed you last year ... we didn't have a prototype, or we didn't know this yet," he said.
For Cuban the best part about getting emails from entrepreneurs is when people email him again years later and tell him that he passed on something that is now a success, but that his critique or advice helped them to succeed.
Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."