What would cause the capacitor to fail in a new 3 speed ceiling fan.

Infant mortality. Happens sometimes. Take it back or get a cap at CeilingFanParts.com Home (http://www.ceilingfanparts.com)

What would cause the capacitor to fail in a new 3 speed ceiling fan.

Oh I don't know, maybe if it got shorted out somehow!

First answer is correct. Second one kind of is-- pullchains short the capacitor when they change speeds.

Try the manufacturer for the new capacitor FIRST, then try the link above.

Ceiling fan capactors - troubleshooting and resources - Ceiling Fans N More (http://www.ceiling-fans-n-more.com/ceiling-fan-capacitors.php)