While quality blenders might be passed down multiple generations, many single-serve modern blenders will eventually fail. Let's troubleshoot the most likely causes of a blender failing to start.
First, verify that your blender is plugged in, and use an outlet that currently works for another appliance. If your outlet isn't working for any device, try reseting the breaker.
The blender might not be able to start because there are too many thick ingredients overloading the cup. Try adding more fluids or removing ingredients below the fill line.
Blade Assembly Failure
The blade assembly is made of two parts typically: blades and bearings. By blending hard objects, blades will dull and cause the motor to work harder and overheat. Blades last an average of 6 months with moderately heavy use. Sharpen or replace the blades if they are dull.
The bearing inside the assembly may also fail from overuse and misuse. Some blenders, like the Vitamix, are intended for running at their max speed in order for the cooling fans to properly work. In some cases, the bearing seal may melt or otherwise disintegrate. Water will then infiltrate the bearings during cleaning and wash away grease and cause rust to form. Replace the bearings or entire blade assembly if the blade won't spin.
Power Button is Stuck or Unresponsive
If the power cord is plugged and has not short-circuited, the power button might be stuck or unresponsive. It's possible that there is grime or other buildup in the switch preventing operation. Try switching on and off to cycle the switch.
Liquids find their way onto and into the motor base. The interface between the cup and the motor base is prone for fluid and grime accumulation. The activators are the three white switches that initiate the blending to begin by locking in the cup and should move up and down with a spring action.. You can test the activators by pushing the three switches down with a flathead screwdriver. If the switches will not move, add a few drops of warm water or vinegar into the activator slots and wait a few minutes before trying again.
A blender that is working too hard processing frozen foods, hard nuts, thick butters, flax seeds, cell phones, glow sticks, etc. will be working harder and may eventually burnout or stall.
Your blender may be equipped with a thermal breaker that shuts down the motor if it starts overheating, so while there's little risk of fire, the blender still might start smoking. If the blender is running for more than a minute on a low power speed, it's likely the motor overheating. Let the blender cool down.