As others have said, you set this toy up and it then does its stuff, with no human intervention required. It is something of a triumph of plastic engineering, all achieved using exactly one chassis powered by one AA battery.
There are a few catches with it. First off, it only works if every single piece is present. Lose one, and the circuit is broken. So it loses a star for that.
Next, unless you assemble it exactly right, with every piece pushed fully home, it won't work. The helicopter is particularly temperamental, and at one point we had to unscrew the base of that part and fiddle with it. Not a big problem, and it only happened once, but my 4-year-old can't assemble this on her own. So another star deducted for that.
Finally, the "post" is actually 12 little plastic balls which some children under 3 will certainly want to eat. So it has to be kept well away from any younger siblings, for instance. No stars deducted for that, because it doesn't detract from the fun potential for an older child, but the "post" itself is likely to get lost over the course of a few months unless you are scrupulous in colecting the balls up after each session. Only balls of the right size will work, too!
With all that said, my daughter is absolutely mesmerised by it...and at the cheaper post-Christmas price, it is reasonable value for the money.