Finding an ideal backpack takes time and can be daunting.
Simply because there are different needs, for instance a sport person will need a backpack that will carry its dirty uniform as well as other stuff such as water bottle, snacks, etc.
And normally sportsman's uniforms get very dirty and therefore their backpacks will get dirty too, this is why they need a backpack that has a canvas bag that is washable.
A college student on the other hand needs a backpack that will carry his books, laptop or any other study material.
This is why students prefer shoulder backpacks, simply because they are very accessible and they look cool too.
Some students prefer backpacks that have wheels; it is a matter of preference choice.
There are also travellers who definitely require a backpack that has wheels, so they can easily move things around with ease (just like some students).
Campers also require backpacks; however their needs are somewhat different they need a very large backpack so they can carry a lot of stuff with them, just like soldiers.
And finally there are people who specialize in certain fields of study that require a backpack of different sizes and shapes for their equipment; they need a backpack that is super stylish for their profession.
These are:

• Beauty Consultants
• Chefs
• Architects
• Engineers
• Doctors
• Labours
• Office workers

These are just a few examples of professional workers who require backpacks that differ but suit their needs when carrying around their tools of the trade.