One of the biggest challenges in condo living tends to be a lack of storage space for owners. Owners might have a small storage unit in the basement if they're lucky, and maybe a bit of extra space in a garage if they're extra lucky. In general, storage seems to be in short supply when it comes to condo living.
As a result, personal belonging often end up in hallways, entrance ways and stairwells. Shoes, bikes and baby strollers tend to collect in these areas. And while owners may have limited personal storage space, personal belongings are specifically prohibited from common areas by nearly every Declaration I've encountered. Common areas are not an appropriate place for your personal belongings and you may be open to fines if you store your stuff anywhere other than in your unit or assigned storage area.
Of course, every association has the right to make exceptions. Before you impose on the space that you share with your neighbors, you should communicate with the Board about whether or not it is permissible to leave anything in a common area.