Packaging should protect the products and its contents. This can be done using hard materials which would be able to be used for that product.
e.g. cardboard for charity boxes
The packaging should inform the buyer of any relevant information such as:
Some information has to be included by law
The packaging must be able to contain all of the product as well as keep it all in place. Things like cereals do this through using a bag as well as a box to protect and contain the product. Sometimes individual components may be used to do this
The packaging must make the product being easily transported to where it can be sold. This must be considered by designers. This is usually done by making the packaging a cube or cuboid so that it can easily be stacked and isn't hard to move. Avoid using circular edges as this will make transporting the product easier.
Many products like foods deteriorate therefore the packaging will have to prevent this. For perfume they make the bottle black to prevent sunlight so the perfume lasts longer. This can be done through other ways like preventing bacteria getting to the product or by making the packaging be tight so that the product can't move around and damage itself.
The packaging must make the customer want to buy the product. It must display the product. This can be done by either having a window in the packaging so that you can see the product or by having an image of the product on the front of it. These will both show the customer what the product looks like.