It's actually a leftover from when I had to process the whole table at once. It's taking the GroupID value from the parent node and comparing it each child to prevent cyclic references. As you're using a single group, the query would have only needed an additional condition.

WITH CTE( groupID, objectType, memberID, [Nodelevel]) as

(

SELECT

tm.groupID

, tm.objectType

, tm.memberID

, 0 as [Nodelevel]

from #Hierarchy tm with(nolock) -- drop table #tblGrpsMatc

where groupID = 8

UNION ALL

SELECT

TC.groupID

,TC.objectType

, TC.memberID

, [Nodelevel] + 1 as [Nodelevel]

FROM CTE C2

inner join #Hierarchy TC with(nolock)

ON tc.groupID = C2.memberID

AND TC.groupID <> TC.memberID

WHERE TC.groupID <> 8

)

SELECT groupID, objectType, memberID, [Nodelevel]

FROM CTE;