In WhatsApp blue ticks indicate that someone has received and read your message. Once they have read your message you expect them to respond immediately. The same goes for people that send you a message, they expect an immediate response. What if you do not want to respond immediately or do not want someone to know you have read their message?
If you are using Android their is a very easy trick to avoid the blue ticks. Add the WhatsApp widget to your home screen. Just long press on a blank space on your home screen to bring up the widget manager. Add the WhatsApp widget to your home screen. Now when a new messages is received, even ones that are several lines long, you will be able to read them in the widget without affecting the ticks. Even if a contact sends you multiple messages you will be able to read each message, rather than reading the the irritating notification ”X unread messages from X” in the notification bar. Of course, if you tap the message in the widget it will launch WhatsApp and the blue ticks will appear.