Error will not catch in try catch block if promise is not awaited

Sometime cannot use await function in a callback, use promise chain will be ok

var process1 = ()=>{
    try{
        promise;
    }catch(error){
        console.log(error);
    }
}

var process2 = ()=>{
    promise.then().catch(error=>console.log(error));
}

var promise = new Promise((r,j)=>{
    setTimeout(()=>{
        j('rejected');
    },300)
})


process1();
process2();