Anyone who lives in society is well accustomed to the expectations of those around them. Some expectations are reasonable, such as being cleanly and polite, so as to maintain sanitation and order within society. There are many expectations put into place for the public well-being, I acknowledge these and agree that they are necessary.
That being said... most expectations go far beyond this and begin to set boundaries between people. For instance, for business and work, one is expected to appear in "formal attire". Well is that supposed to mean? Where did the notion that a suit and tie is more formal than a t-shirt and jeans come from? It certainly wasn't natural... humans made it up. It is an article of clothing meant to embellish the egos of those on "official business". A businessman with a brilliant idea but a silly dress would surely be taken as no more than a joke. These expectations are imposed upon people to make them feel like their obligated to learn to act or speak a certain way, or buy certain products. Then this plays into another factor of such societal expectations: marketing.
Traders and such people back in the day and even more so now are compelled to use expectations against people in order to get them to buy a product. You have to buy a suit to be successful. You need to buy makeup and perfume to look good and be popular. You have to buy a ring to show your love to your significant other. How did that tradition come along anyways? In what way is the giving of a rock a better display of affection than a simple hug? If anything tying your attachment to another in the form of an object seems superficial. Exchanging an object to remember eachother by is fine, but why does it have to be a rock? And why such an expensive one? Marketing and human greed, that's why.
Those were some of the more physical expectations of society, but what about the social ones? Women grow up learning that they need to look pretty, and that they need to care about their image more. This makes them more conscious about how they look and what those around them say. I have a friend who struggles with this, she doesn't like guys, but wants guys to like her simply for the social status that gives. Men, on the other hand, care less about what others say to them, they like to joke around and insult eachother, but they usually do not display their affection for eachother the same way girls do- in the form of hugs and other physical gestures. The most a guy usually does is a handshake, fistbump, or punch to the gut. Gender roles and proper actions are determined in society, but why in the form that they are?
We adhere to many societal expectations on a daily basis without further consideration because it seems normal to do so. However, if one takes a moment to stop and think about them, many of these expectations seem odd and seemingly illogical.