Stimulate the product visually to the potential customer.
These products are normally very elaborate and have several stages to their production.
It can take several days to produce just one product and it is just because the professional pastrycook or patissier has the storage capacity to produce and store these components that they are sold at a very competitive price.
Some gateaux are traditional but modern day interpretation offers a much wider selection to the consumer.
A gateau was normally based on sponge cakes that had three layers of sponge and layers of cream and flavoured syrup. The syrup was to replace moisture in the sponge that was lost due to staling.
Tortes where originally pastry based with a filling inside and another mixture might act as a topping over the filling.
All things evolve over time and with modern communications many lines are blurred.
Staling is a term that describes loss of moisture from starch based product such as bread and cake: