My guess would be that the assessment forms are fairly complex.

1) Has the animal ever acted aggressively? Y_ N_ (if yes, don't spend time you don't have trying to determine why, i.e. someone taunted it, hurt it, etc ... kill it)

2) Does the animal appear to be nervous around children? Y_ N_ (if yes, this might be the result of lack of socialization around children or a behavioural problem. Best to err on the side of caution ... kill it)

3) Is the animal elderly? Y_ N_ (if yes, consider the stress the animal may experience when/if introduced to a new home. Staff needs to determine if the animal will be able to adapt, if staff is uncertain ... kill it)

4) Has the animal been acting agressively since being placed in an overcrowded kennel with another animal it's not familiar with? Y_ N_ (if yes, this indicates the animal is unable to adapt to new situations ... kill it).

The above aren't from the real assessment form, but it probably isn't too far off the mark.