For a sequence $u_j:\Omega\subset \R^n\to \R^m$
generating the Young measure $\nu_x, x\in\Omega$, Ball's Theorem
asserts that a tightness condition preventing mass in the target from
escaping
to infinity implies that $\nu_x$ is a probability measure and that
$f(u_k)\rightharpoonup\langle\nu_x,f\rangle$ in $L^1$ provided
the sequence is equiintegrable. Here we show that Ball's tightness
condition
is necessary for the conclusions to hold and that in fact
all three, the tightness
condition, the assertion $\Vert\nu_x\Vert=1$, and the convergence
conclusion, are equivalent. We give some simple applications of this
observation.