Like every other government agency in India, India Post also sometimes has its fair share of negligence and delay directed towards its customers. Sometimes, their services are unable to certain towns or regions due to the unavailability of a Post Office in that area. Private courier services however, make it their primary duty to deliver even in remote areas.
This is also owed to the popularity of private courier services. Since e-commerce sites (such as Amazon, Flipkart or Ebay) have tie ups with the private courier companies for mutual benefits. Hence, whenever we buy something online, we get to know that XYZ Courier service does a good job. You should also know how Amazon’s temporary shift to India Post didn’t end so well with extreme delays in delivery and non-responsive delivery men.
So, other than the laziness factor, India Post provides pretty decent services for low prices. Speed post provides far better services but in times of urgency, people just tend to rely on the reliable private services.