auto refresh on materialized views - what am I missing ?

I am creating a materialized view on another schema's table to use.  I want it to refresh daily.  I have reviewed the documentation butam missing something, as it doesn't autorefresh.

Here's what I have.   I created a materialized view log on MG.TIP  table.  as
            Create materialized view log on MG.TIP  .. 
             with primary key excluding new values;  

then here is my materialized view in the  GHM schema

Create materialized view "GHM"."TIPP_VEW"  (value1, value2, value3)
..
build immediate
using index.
refresh force on demand start with sysdate+0 next (sysdate +.25)
using default local rollback segment
using enforced constraints disable query re-write