Kylie Jennerfaced backlash from fansafter posting a video of herself washing her face for only 10 seconds to promote her newKylie Skin Foaming Face Wash.

While many people tweeted at the 21-year-old star to say that she should be cleansing her skin for about 30 to 60 seconds in order to remove all makeup and residue, PEOPLE turned to a leading N.Y.C. dermatologist and founder ofSobel Skin,Dr. Howard Sobel, to get the low-down on Jenner’s technique.

“Kylie did not properly cleanse her face for the right amount of time,” Sobel tells PEOPLE. “She neglected certain areas and it appears she was a little harsh on her skin as well.”

Kylie Skin/Twitter

Kylie Jenner face washing

Sobel says that “while your face washing routine doesn’t need to be very long,” he does recommend “putting in more effort than 10 seconds,” which is what Jenner did in the video posted on the Kylie Skin Instagram and Twitter page.

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“It should take you 20 to 30 seconds to wash your face each morning and night,” he says. “However, if you are exfoliating that will usually takes around 60 seconds.”

According to Sobel, in the evening, people should actually use a two-step method in order to fully cleanse their face before bed.

Kylie Jenner face wash

As for the best face washing technique, Sobel recommends using motions that are as gentle as possible.

“Start in your problem areas as those need the most attention and use your fingers to rub in a gentle cleanser with lukewarm water,” he says. “Use circular motions to remove any residue and prep your skin. Make sure to always push your hair back and cleanse your hairline, too!”

source: people.com