It makes sense that fifteen minutes a day of Duolingo isn't as effective as spending two hours a day studying, going to meetups, traveling to a foreign country, etc.
I recall similar criticism for the "seven-minute workout" from people who pointed out that joining a gym and hiring a personal trainer is a more effective way of getting in shape.
But those are not very helpful. If I have fifteen minutes before the kids wake up my only decision is how to spend that time. Duolingo? Meditate? Pushups? Half an episode of something? Daydream?
I recall similar criticism for the "seven-minute workout" from people who pointed out that joining a gym and hiring a personal trainer is a more effective way of getting in shape.
But those are not very helpful. If I have fifteen minutes before the kids wake up my only decision is how to spend that time. Duolingo? Meditate? Pushups? Half an episode of something? Daydream?