The base it's falling on is the answer.
If you're likely to leave the piste (even by a few metres), then you need to read this.
Experts, in many parts of The Alps, are warning that the last few weeks of generally cold and clear conditions have left a base snowpack that will not easily bond with any new snow.
Henry (of Henry's Avalanche Talks) has this to say :-
Sometimes a bit of time helps the snowpack to settle and strengthen. This is NOT the case at the moment in the Northern French Alps.
Each day (and especially cold night) that has gone by, without snowfall over the last 3 or 4 weeks, has made the snowpack less consolidated. It has made the skiing nicer the more sugary the snow has become BUT with the next snowfall on top, this current sugary snowpack will be a very, very weak layer underneath. If you are not thinking about what you are doing and applying basic avalanche safety/prevention measures, it will be very dangerous.
...and has posted this video taken a few days ago...
See Attention Off-Piste and Touring Enthusiasts from HAT.
The unpredictable nature of the current base (ahead of fresh snow expected today) has been tragically illustrated already this week with a fatal avalanche in Lech (with prevailing Avalanche Risk Level at the lowest - Level One).
There are more observations from PisteHors :-
Conditions at the moment are very similar to the start of the 2005 / 2006 season which saw a record 57 avalanche deaths in France. A thin snow-pack with very strong temperature gradients. On all slope aspects except south the snow pack is composed of a weak faceted layer.
Stay safe - don't think it'll never happen to you; do some research (on the excellent resources linked to above), attend one of the numerous free talks around The Alps, and get educated (and equipped).
And always... take local advice before leaving the piste.