Why globular proteins have hydrophilic amino acid on the outside and hydrophobic amino acid on the inside?

Question

Why globular proteins have hydrophilic amino acid on the outside and hydrophobic amino acid on the inside?

Answer 1

Think about where you can find these proteins: in blood. and think what is the blood mostly made of: water.

Now think what hydrophilic and hydrophobic mean: water loving and water hating, respectively.