In essence, it’s the point where you reach financial independence or FIRE (financial independence/retire early).
With fairly consistent annual expenses in the $52-$54k range, we are getting close to the crossover point (ie. financial independence).
While I don’t plan on retiring quite this early (I’m still 25 in my mind), it’s a reassuring financial backup plan if something were to happen that impacted our main income stream (ie. losing my job, poor health etc).
For example, going for $40k in dividend income, assuming 4% yield, would require a $1M portfolio; $60k in dividend income requires a $1.5M portfolio; and $100k in dividend income would require a $2.5M portfolio.