During titration, it is very common to have some NaOH spilled to the inside wall of Erlenmeyer flask. Ideally, these spilled NaOH should be washed down, but most students (if not all) did not do so. How will these NaOH on the wall affect the experimental result?

Since these spills will make the volume of NaOH artificially higher, it will make the experimental result higher as well.
Since these NaOH did not have a chance to react with acetic acid, it should not affect the experimental result.
Since these NaOH did not have a chance to react with acetic acid in vinegar, it will make the experimental result lower.