Most of the programmers and software engineers work in the IT Sector. IT Sector is pretty new sector when compared to other sectors like Manufacturing, Retail, Shipping, Education etc.
Changes in IT Sector and IT Sector driven changes in other sector are quite faster. So whoever works in IT sector has a need to be latest in his/her domain. Something like a Doctor. Doctors needs to keep on updating themselves on a daily basis on the new medicines that are coming up, new machines or tests that are coming up, new combination of diseases that are coming up.
Similar to that for software engineers, knowing and learning new technologies is a need of the hour. If you are a programmer in PHP or Java and if you do not know what latest changes / features that have come in the last quarter in the language, applications and technologies, you become obsolete very fast. That is one of the main reasons why those who are looking for jobs in IT sector and those who are working in IT sector needs to continuously upgrade the skills.
Now updating about latest skills in technology sector is not easy as there will not be any training institutes or training programs on the new technologies. You can definitely get training institutes in the old technologies but definitely not in latest and new technologies. If some training programs exists they may be of fundamental in nature or very expensive.
So there is tremendous need for companies to have employees who can read books on the new technologies on their own and develop abilities to apply them in their software development assignments.
To be very specific, let us say you are a mobile application developer in the android platform. You need to first know most of the features of an android phone so that when some assignment is given to you, you have capability to understand. But for the same android phone, you don’t need to know all the features if you are just a user.
On top of that you also need to know all the latest bug fixes that have come and the APIs that are available so that you are quick in delivering your work once a task is assigned. If you do not have a reading habit, you will start searching for solutions online or you will start learning about android new features after the task is assigned. This will significantly delay the delivery times of your team and your company. And obviously your company will be at loss if you do not continuously read and update yourself on technologies.
So if programmers and software engineers do not have reading habit they become obsolete sooner than later.