Implicit waits are used to provide a default waiting time between each consecutive test step/command across the entire test script. Thus, subsequent test step would only execute when the specified amount of time have elapsed after executing the previous test step/command.

Why do we use implicit wait?

Implicit wait is used in the program when you are sure about the time taken by all web-elements on the web-page to load/visible and for certain Web-elements which you find time as one the varying factor in it's loading then you can use explicit wait.

Why do we need implicit wait in Selenium?

The Implicit Wait in Selenium is used to tell the web driver to wait for a certain amount of time before it throws a “No Such Element Exception”. The default setting is 0. ... It means that if the element is not located on the web page within that time frame, it will throw an exception.