Mark Cuban, HDNet founder now mostly known for owning the Dallas Mavericks and host of reality TV series Shark Tank, took to Reddit on Christmas Eve for an Ask Me Anything session. Just as he appears on the show and when making statements about the NBA, Cuban was direct and candid when answering questions, providing some amusing anecdotes and informative insight.A number of the questions and answers had to do with Shark Tank, where Cuban revealed some behind-the-scenes facets of the show. Fans of the show would note that there is quite a bit of T-Mobile product placement going on, and Cuban agrees, saying none of the hosts of the show enjoy it. Because this AMA was handled on the internet, someone responded with a montage of some of the more egregious T-Mobile product placements, which you can be embarrassed about and watch here. Cuban also revealed that even if an entrepreneur’s idea gets accepted, about 25% of them fall through after the camera’s stop rolling, due to a wide assortment of issues that end up being discovered, from people not paying their taxes to straight up lies about the idea. He also said that the only investment he’s ever made on Shark Tank that lost him money was Toygaroo, which is essentially a Netflix for toys.Cuban spouted some other fun lines, such as when someone asked him what a billionaire buys his kids for the holidays, he said “The same junk that everyone else buys.” He later said the most expensive gift he bought anyone for Christmas this year was under $200, and he also said he’s part of Amazon Prime in order to get better rates.He also brought his famed sarcasm to the AMA, responding to several sports-related questions with witty remarks. When asked what he thought David Stern was — the current commissioner of the NBA that Cuban has publicly clashed with many times — Cuban simply said “a great tailor.”Cuban also said he’s taken a look at Major League Gaming and finds it interesting, though he hasn’t spent enough time checking it out as of yet. He answers some more questions, including a bunch about the NBA, so head on over there and give it a look.