General conscription (from the Finnish goverment's Defence White Paper)

The defence of the entire country is only possible if general conscription is maintained. The high educational standard of conscripts makes it possible, with the current periods of service, to provide conscript training in even the more demanding tasks, and to recruit high-quality personnel for international crisis management tasks and for the professional personnel posts in the Defence Forces.

Due to conscription, the obligation to defend the country can be met equally throughout society. At the same time this creates a foundation for the strong will of citizens to defend their country and for commitment to national defence. It also guarantees transparency of the Defence Forces' activities in society at large.

By training conscripts of a similar young age in each intake, it is possible to maintain the age structure of the operational forces at a low enough level and at the same time ensure a sufficient reserve in staff, support and local defence duties.
Defence White Paper 2004
http://www.defmin.fi/chapter_images/2160_English_White_paper_2004.pdf