[SalesForce] Workflow Field Update formula function TEXT() using picklist API values, not label values

https://success.salesforce.com/answers?id=90630000000CijDAAS

this functionality isn't available with workflows. You can't update a mult-select picklist through a field update. For this, you will need to utilize an apex trigger.

Starting from the Spring'15 you can update Multi-Select Picklists using Process Builder

http://releasenotes.docs.salesforce.com/en-us/spring15/release-notes/rn_forcecom_process_ui_updates.htm#multi-select

Use Multi-Select Picklist Fields

Previously, you couldn't select multiple values for any fields. Now you can do so for fields that accept more than one value. For example, if an action creates a record and the record has a multi-select field, you can select multiple values for the multi-select field.

Multi-Select Picklists in the Process Builder

For example, set multiple values for the Country field for a company record that operates in Ireland, the UK, and France.

You can use multi-select picklists in:

• Formulas
• Process criteria
• Create a Record actions
• Quick Actions
• Update Records actions

In process criteria, set multiple values by creating one condition for each individual multi-select picklist value. For example, if your process checks whether changes were made to an account’s office locations, reference multiple values by choosing the same field for each multi-select picklist value.

Refer to Tips for Working with Picklist and Multi-Select Picklist Formula Fields for more information. When you reference a multi-select picklist field in an action, enter values by clicking Choose values… Add or remove values by dragging them between the Available (1) and Selected (2) columns.

Keep these considerations in mind when using operators with multi-select picklists.

• You can use the Equals operator if you select only one value from a multi-select picklist field.
• If you use the Equals operator with multiple multi-select picklist values and choose the Any of the conditions are met (OR) option, the condition matches on one value only. For example, if your process checks whether a Region field equals West or East, the condition evaluates to true when the value is West or when the value is East, but won’t evaluate to true when both West and East are selected values.
• If you use Contains and OR to evaluate multiple multi-select picklist values, the condition evaluates to true on multiple values. For example, if your process checks whether a Region field contains West or East, the condition evaluates to true when a Region field contains West and East or when a Region field contains West or East values.

Source: - Multi-Select Picklists in the Process Builder

Well, aside from the AND being extraneous, you need to add an ISNEW check to your OR clause if you want it to fire on create. The ISCHANGED formula returns false on create.

OR(ISNEW(), ISCHANGED(Field1), ISCHANGED(Field2), ISCHANGED(etc))