Most people who practice Aikido encounter it as grown members of society.
The age at which they start training and their past exercise or sports experiences vary. Yet, these do not seem to link clearly with their progress in Aikido. It seems that many people who do not enjoy competitive sports still find that Aikido is suitable for them.
Also, the points of emphasis and practice content in Aikido vary depending on the instructor or dojo. Past experiences can even get in the way (especially in the case of bad habits).
Alternatively, people with no experience will have no fixed ideas or bad habits about Aikido. They can start the practice with a blank state, which may actually be a strength.