Simplify the following text for a Grade 12 native English-speaking person.
Original: Although the minimum stadium capacity for category four is 8,000 , no stadium with a capacity less than 40,000 has been selected to host a UEFA Europa League Final , and no stadium with a capacity less than 60,000 has been selected to host a UEFA Champions League Final , since these regulations were introduced in 2006 .
Simplified: Although the minimum stadium capacity for elite categorisation is 30,000 , no stadium with a capacity less than 40,000 has been selected to host a UEFA Europa League Final . No stadium with a capacity less than 60,000 has been selected to host a UEFA Champions League Final since these regulations were introduced in 2006 .