Being honest is hard and it is easy. It is hard because sometimes being honest can hurt somebody else or hurt you. It is easy because if you are honest, you have nothing to hide and nothing to be afraid of.
There is time and place to be dishonest, for example if being honest can cause real harm (e.g. hiding Jews in a cellar during WWII and Nazi asking you where they are). But in general, honesty, while creating short term discomfort, will lead to long term alignment.
Dishonesty creates misalignment, miscommunication and distrust. Dishonesty is to be used mainly against your enemies, not against your friends and colleagues.