In this report, the arguer avers this trend in the future: the chain of stores that sell supplies for do-it-yourself home improvement will welcome to an increasing demand for products with big profits in the coming years. To substantiate it, he lists three arguments, such as compare between sales of new houses and that of existing ones, assumption of growing inclination of improving houses and so on. Nevertheless, the arguer's argument is problematic in several respects as following, rendering the argument unconvincing as it stands.
The beginning problem in this report is that the phenomenon of decrease in sales of new houses and meanwhile increase in that of exiting houses has no direct consequence relation to popularity of making repairs or improvements without sufficient evidences. Here, the arguer imagines that the saved money by purchasing second-hand houses is definitely spent on home improvement, which is based on few facts. Maybe it is the decline of average income that generates the popularity of buying existing houses. Maybe the more money left by not buying new houses is finally spent on other respects, such like nutrition improvement, offering children higher intuition and so on. Hence, if not ruling out these possibilities above, the arguer cannot construct the cause-effect relation between them through his own reasons.
Secondly, even if the consequence relation above exactly exists, that is more sales of old houses than new ones really lead to the increased percentage of homeowners who will be making repairs or improvements to their homes, the arguer cannot assume that the kind of homeowners are more likely to make improvement themselves. Perhaps most homeowners prefer purchasing a set of furniture from factories directly to buying lots of parts from the DIY stores, for people on the work always don’t have free time to improve home. Perhaps part of homeowners who like manual apparatus will employ workers in improving companies to finish the job. Therefore, the arguer’ assumption about people purchasing existing houses are the one who enjoy DIY.
Finally, even though the factors the arguer points above are all right, these factors just worked out in the past and the he cannot be sure that this trend will continue in the coming years. Common sense indicates that everything is changing. Perhaps in the next years, homeowners incline to purchase new houses rather than existing houses. So, he is too arbitrary to reason that factors in the past will influence the present and future.
To sum up, the arguer's argument is unconvincing. To bolster it, he must provide clear evidences that could avoid the three logic flaws in the last three passages. Not until does the arguer offer rigid the process of reasoning, I cannot believe his conclusion that the chain of stores that sell supplies for do-it-yourself home improvement will welcome to an increasing demand for products with big profits in the coming years.