Why do people say "like" instead of "love"?

Because both words can be defined differently between people. For example, if someone shows affection to someone, but not on the level they think is love, they'll moreover say that they like that person.
It depends on how the individual defines these words.

cause 사랑 is a strong word

It doesn't mean the same. 사랑 is harder to get. Like is 더 많이 like "appreciate". 사랑 is something much stronger.

사랑 and like are different things. Just because 당신 like someone does not mean 당신 have strong feelings for them.

Read the other 답변 ._.


But, like isn't as strong as love....

They don't.

When they mean love, that's what they say.