Why does the Flight log report inaccurate figures?

[Endersmens]

How come when my G meter clearly reads 10-15+ Gs, after pressing f3, my flight log shows max G force and it's a lower number than what I have observed? Same goes for speed, I can be going 3,000 m/s and flight log shows a max speed of a lower value. Even when surface speed is used.

Does it have to do with how long a force is exerted? If I experience a quick jump in G force and then it goes away, it's like it didn't happen. Is there any reason for this?

 

I haven't provided logs or anything because it's a fairly common problem that can happen to anyone, has happened to me on all my installs, stock or not.

[Guest]

It's a really weird thing.  It's almost always inaccurate.  I personally think it needs to be looked into, yet never changed, similar to stock ∆V and TWR readouts.