Hello @booramaravind
The data wrangling can become a very complex issue. We cannot answer with a single reason on why the automated selection interpreted one or the other format, without a detailed revision of the source and a process description on the data generation.
We cannot see the whole dataset in your pictures; The workflows that you shared are neither useful aiming to clarify your question, as the data is not embebed in the data section. Despite I can identify a CSV format sourcing the workflow based on the CSV reader 
I would ask some questions regarding the CSV source, like:
- Was it generated as an output of a DB query?
- Does it need some specific encoding type?
- Was it originally an excel converted into CSV for some specific reason?
- If it was an Excel, was it a collaborative document?
- If it was collaborative, there were different regional configurations working with the document? And if do so, who saved it last?
…
Why all this is important? Because when your column is not interpreting the the expected data content, then the way you process it, can lead you to loss of information issue. Some of them are easy to fix, some other are not that easy.
When you enforce a column to read numeric, it can lead you to a loss of information issue (guess part of the information stored as double, with comma 6,0 decimal or as text “150”), in this case this information will be replaced with nulls.
Reading the data as string preserves all the information but affects to the usability of the data, as extra manipulation is required further to fix the issue.
I’ve prepared a CSV with some of the typical issues interfering when reading from uncontrolled sources:
My suggestion is to spend some time trying to understand the origin of the issue, and judge the better digest approach. In the above example I could enforce to numeric for columns 1 and 3(!), but maybe is not a good approach for columns 2 and 4, where some action may be expected: or in the process, or in the source itself, or in the reading configuration, or post reading transformations …