What does vesting mean?
Vesting is the process by which employees gradually earn the right to their shares or options. A typical vesting schedule spans 4 years with a 12-month "cliff" (you only start vesting after 1 year).
Why does vesting exist?
Vesting ensures that employees stay with the company for an extended period before gaining full access to their shares. It protects the company from giving away ownership stakes to people who leave early.