Strongest Versus Weakest

ATR commented jewishanswers.org:

The star is reaching out in all directions and anchored by a central point, I would surmise to be the Torah. Each of the six lines of the star is attached to another, and stands upon a foundation. The whole star system is very powerfully supported in its design.
You might contrast this with a swastika, which also has six lines, and without support or anchor. The Mogen Dovid is the strongest and most supportive thing you can do with six lines. The swastika is the weakest.