You are setting the label text to strStudy
each time. This doesn't add to what's there already, it just replaces it.
You need to add strStudy
to the text that already exists, something like this:
' start with an empty string
lblMotivation.Text = ""
For intCounter = 1 To intNumber Step 1
' append the study string and a newline
lblMotivation.Text = lblMotivation.Text & strStudy & Environment.NewLine
Next