To avoid being followed by strangers
Some people dislike being followed by people they don’t know, so they make their accounts private.
They don’t want certain people to see their accounts
Some people try to hide their social media accounts from some people. Making their Instagram private helps with that.
They like being in control
People who like being in control can make their Instagram private so that they control who can see their posts.
They are celebrities
Some celebrities make their personal Instagram accounts private so that fans don’t invade their account. (See Why do celebrities use Instagram?)
They want to post pictures freely
Some people make their Instagram account private so that they can post whatever kind of pictures they want.
To avoid being followed by spam accounts
Making your Instagram account private ensures that you don’t get followed by spam accounts.
To avoid having their pictures stolen
Some people suffer from having their pictures stolen and people creating fake profiles with them. Making Instagram private prevents that problem from happening.
They don’t want people to know about their private lives
Some people appreciate privacy, which is why they choose not to make their Instagram public. (See Why Do People Care About Online Privacy?)
To avoid harassment
Some people experience harassment on Instagram due to their sharing certain photos. This drives people to make their accounts private.
To hide it from their family
Some people make their Instagram accounts private so that their family can’t follow them.
They don’t care about the number of followers
Some people create Instagram accounts to share pictures with a close group of friends. They don’t pay much attention to their number of followers.
To not be judged by people
Some people hate being judged by others. Making their Instagram private is one way of avoiding judgment.
Why do some people hide their Friends list? Why do people on Facebook hide their Friend list?