Really depends on the list of things for which you require a workflow.
There is a standard leave Request Process available on ESS - workflow will route it to manager and on approval, will automatically update the Absence Infotypes. There are standard ESS services for a variety of infotype updates such as Addresses, bank Details etc. These do not require any approval, they will directly update the infotypes. HR Processes and Forms offer a way of having your own processes for a variety fo scenarios. You are able to customise the workflow as you require.
This is a generic answer to this question.