All animals in this category are for special and/or urgent adoption because of one or several factors.
The animal may be shy or scared because, for example, it may have been badly treated in the past. It may need special conditions, like living inside a house or may require some kind of psychological work or treatment.
Or an animal may not be social with other animals (even if it is gentle with people) and may only go to a house where there are no other animals.
An animal may also have some physical deficiency or be suffering from some illness.

Give a chance to these animals. They will be grateful and you will be happy.