DAO when to use suspend function android

I am following DAO tutorial on Android developers here:

https://developer.android.com/codelabs/android-room-with-a-view-kotlin#5

They say:
By default, all queries must be executed on a separate thread.
Room has Kotlin coroutines support. This allows your queries to be annotated with the suspend modifier and then called from a coroutine or from another suspension function.

Dao interface is as follows:

@Dao
interface WordDao {

    @Query("SELECT * FROM word_table ORDER BY word ASC")
    fun getAlphabetizedWords(): List<Word>

    @Insert(onConflict = OnConflictStrategy.IGNORE)
    suspend fun insert(word: Word)

    @Query("DELETE FROM word_table")
    suspend fun deleteAll()
}

Why getAlphabetizedWords() is not defined as suspend function?

In coroutines, a flow is a type that can emit multiple values sequentially, as opposed to suspend functions that return only a single value. For example, you can use a flow to receive live updates from a database.

@Dao
interface WordDao {

    // The flow always holds/caches latest version of data. Notifies its observers when the
    // data has changed.
    @Query("SELECT * FROM word_table ORDER BY word ASC")
    fun getAlphabetizedWords(): Flow<List<Word>>

    @Insert(onConflict = OnConflictStrategy.IGNORE)
    suspend fun insert(word: Word)

    @Query("DELETE FROM word_table")
    suspend fun deleteAll()
}

you can see source code in Github.