In spite of Data Warehousing (DW) needs a large amount of contribution, still Data Warehousing is getting a good hype in the market. On the other hand, most of the DW resources fail at the end. However, here the authors argue about the maturity of a Data Warehousing Process (DWP) which could somewhat come together with large-scale failures and get the confirmation about the process, better quality, \"Single-version of a true fact\" data in a sequence order. Though, the assessment of DWP maturity has not been overtaken in a systematic way, unlike software development. In spite of crucial level of priority of data as a corporate initiative, the necessity of a maturity model for DWP won't result in a great manner.