Is it okay to return so many promises in both components?.

I have deferred in the services and in the controller. the code is well established or should do in the service simply a return with everything. What other things do you propose to improve the code?

controller:

function mostrarResultado(publicKey, pago, metodoPago) {     var defer = $  q.defer();      tarjeta.mostrarResultado(publicKey, pago, metodoPago).then(function (respuesta) {         console.log("response vault: " + respuesta);         defer.resolve(respuesta);     }, function (error) {         console.log("Error MercadoPagoPlugin : " + error);         defer.reject(error);     });      return defer.promise; }  

service:

function mostrarResultado(publicKey, pago, metodoPago) {              var defer = $  q.defer();              MercadoPago.showPaymentResult(publicKey, pago, metodoPago, success, failure);              function success(response) {                 console.log("response vault: " + response);                 defer.resolve(respuesta);             }              function failure(error) {                 // Error llamando a MercadoPago Plugin                 console.log("Error MercadoPagoPlugin : " + error);                 defer.reject(error);             }               return defer.promise;          }