Here's why:
* Clarity: "Because" can sometimes create ambiguity, especially in complex sentences.
* Flow: Starting with "because" can sometimes feel like the sentence is starting in the middle of an explanation.
* Style: It's generally considered more sophisticated to vary sentence structure and avoid starting too many sentences with the same word.
However, it's not *always* incorrect:
* Emphasis: You can use "because" at the start of a sentence for emphasis, especially in informal writing or speech.
* Natural flow: Sometimes, the sentence simply flows better that way.
* Literary devices: Writers often use "because" at the start of sentences for stylistic effect.
Examples:
Less formal:
* Because I was hungry, I ate a sandwich.
More formal:
* I ate a sandwich because I was hungry.
Emphasizing:
* Because it was raining, we had to stay inside.
Ultimately, the choice of whether or not to start a sentence with "because" depends on the context, your audience, and the desired tone of your writing.