why is it important to be gentle when streaking a bacterial

why is it important to be gentle when streaking a bacterial culture onto agar media?

Solution

If the culture sample is spread gently, the bacteria can be evenly spread on the surface of the culture. Rough streaking make the bacteria to dig in the culture, so it can survive only if it an anaerobe. Also, all the bacterial sample may be restricted to one site if the streaking is rough.