From Eric Barker's blog: "Research shows self-esteem doesn’t cause all those good things. It’s just a side effect of healthy behavior. So artificially boosting it doesn’t work." From Kristin Neff's Book Self-Compassion:

In one influential review of the self-esteem literature, it was concluded that high self-esteem actually did not improve academic achievement or job performance or leadership skills or prevent children from smoking, drinking, or taking drugs. If anything, high self-esteem appears to be the consequence rather than the cause of healthy behaviors.

What does raising self-esteem do? It probably increases narcissism. So what do we need instead of self-esteem? Self-compassion. Stop lying to yourself that you’re so awesome. Instead, focus on forgiving yourself when you’re not. In my upcoming book I talk about why self-compassion beats self-esteem.

So why does compassion succeed where self-esteem fails? Because self-esteem is always either delusional or contingent, neither of which lead to good things. To always feel like you’re awesome you need to either divorce yourself from reality or be on a treadmill of constantly proving your value. At some point you won’t measure up, which then craters your self-esteem. Not to mention relentlessly proving yourself is exhausting and unsettling. Self-compassion lets you see the facts and accept that you’re not perfect. As famed psychologist Albert Ellis once said, “Self-esteem is the greatest sickness known to man or woman because it’s conditional.” People with self-compassion don’t feel the need to constantly prove themselves, and research shows they are less likely to feel like a “loser.”