How does titration affect molarity?

Hint: Molarity is defined as the number of moles of a species present in$1000ml$or$1l$of a solution, it is a stoichiometric measure of quantity of a substance.
Titration is a common laboratory method wherein quantitative chemical analysis is used to determine the concentration of an identical analyte.

Complete answer:
 When we perform titration on say $Yml$of analyte we add a certain amount of titrant to it so that a reaction between these two species occurs which results in the formation of a product that makes its presence detectable either via color change or some other observable change. During this whole process we add more and more of a solvent into the already present solution whereas the amount of the substance whose concentration is to be determined is still constant or less than the initial amount thus this would lead to dilution. Upon dilution only volume increases and as we know that concentration in terms of molarity is the ratio of moles of the substance present in the total volume of the solution therefore the overall molarity would reduce as titration proceeds.
Thus, upon titration the molarity of a substance decreases as time passes by.

Note: When talking about a certain species and its concentration in the solution during titration we must note that the species may still have a constant amount even after titration or it may have an amount lesser than the initial one thus not only volume is increasing during titration but also the amount of the substance whose concentration is to be measured has reduced which decreases the Molarity even more drastically in the solution.