Redundancy:
* "Bit" already implies a small amount: "A little" is already a quantifier indicating a small amount, so "bit" adds little extra meaning.
* Formal writing: In formal writing, "a little" is often preferred over "a little bit" for a more concise and sophisticated style.
When "a little bit" is appropriate:
* Emphasis: Sometimes "a little bit" emphasizes the smallness of the amount more than "a little" alone. For example, "I'm a little bit tired" emphasizes the tiredness more than "I'm a little tired."
* Informal language: "A little bit" is common in informal spoken English and can sound more natural than just "a little."
* Specificity: In some contexts, "a little bit" can be more specific than "a little." For example, "He's a little bit nervous" might be more precise than "He's a little nervous."
In conclusion:
"A little bit" is not inherently wrong, but it's often redundant. Whether you use it or not depends on your intended meaning, the level of formality, and the overall tone you want to convey.