There is no guarantee that rows will be returned in any particular unless ORDER BY is specified.
There is also no guarantee that rows will be inserted in a particular order, even if the inserts are sourced as SELECT...ORDER BY...
For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden