In less than a year, Nintendo managed to sell more Switch consoles than their lifetime sales of the Wii U. With almost 15 million units sold in 2017 compared to the 13.5 million of the Wii U, the hybrid Switch console is already considered to be a major success.
https://www.notebookcheck.net/In-less-than-a-year-Nintendo-Switch-has-surpassed-Wii-U-s-lifetime-sales.280620.0.html