We show that the absence of outbursts during low states of VY Scl stars is easily explained if white dwarfs in these systems are weakly magnetized ( \mu \mathrel { \hbox to 0.0 pt { \lower 3.0 pt \hbox { $ \mathchar 536 $ } \hss } \raise 2.0 pt% \hbox { $ \mathchar 318 $ } } 5 \times 10 ^ { 30 } G cm ^ { 3 } ) .
However , some of the VY Scl stars are observed to have very slow declines to minimum and similarly slow rises to maximum .
The absence of outbursts during such intermediate ( as opposed to low ) states , which last much longer than typical disc ’ s viscous times , can be explained only if accretion discs are absent when their temperatures would correspond to an unstable state .
This requires magnetic fields stronger than those explaining outburst absence during low states , since white dwarfs in this sub-class of VY Scl stars should have magnetic moments \mu \mathrel { \hbox to 0.0 pt { \lower 3.0 pt \hbox { $ \mathchar 536 $ } \hss } \raise 2.0 pt% \hbox { $ \mathchar 318 $ } } 1.5 \times 10 ^ { 33 } G cm ^ { 3 } i.e .
similar to those of Intermediate Polars .
Since at maximum brightness several VY Scl stars are SW Sex stars , this conclusion is in agreement with recent claims about the magnetic nature of these systems .