One of the most common aspects that IT students struggle with initially is how detail oriented one has to be. If you write a program and one of the variable names is off by one letter, your program will not work. If you write an SQL query and you leave out a single quote at the end of a string, your query won’t work. If you enter an IP address and it is off by one number, the computer can’t be reached.
The reason we have to be so precise is that computers are not (yet) capable of inferring your intentions in most situations (there are some tools for specific cases such as autocomplete and code completion) and it has to be exactly told what to do. Naturally, this can be frustrating but I also believe it can turn into a very valuable skill. Here are some of the benefits of paying attention to detail:

1. You need to pay attention to detail to be successful in IT. I gave some example in the previous paragraph but there are many more, of course.
2. It musters discipline. Paying attention to detail essentially comes down to being disciplined in several ways. See the paragraph below for some tips on how to get better.
3. You will come across as more professional. Your emails will look better because there are fewer mistakes. You won’t forget to send thank you notes after interviews. Your software won’t crash in production because you envisioned all possible scenarios that could go wrong. These are just a few examples.
4. Many important things in life require precision. There are many examples but, for example, you better make sure that you understand all the details in any contract that you sign (e.g., a mortgage).

What can I do to become more detail oriented?
The most important thing is to review your work. This means that before running your programming you read through the code again and check for mistakes. Or before submitting an assignment you proofread it. Or before sending an email that you check for spelling and grammar errors. In addition to reviewing your work, it is also important to work without distractions (e.g., see here). Another way to avoid mistakes is to start early and avoid rushing assignments and stress (e.g., see here).