Larry Putnam, Jr. recently presented a short tutorial on the benefits of Top-Down Estimation for Software Projects:

• Top-Down Estimation methods provide the data needed to make early decisions because most software project schedule and cost decisions are made early in the project or product lifecycle 
• Savings Associated with Top-Down Estimation
• Top-Down Estimation vs. Detailed Planning
• Sum of the Parts Don’t Equal the Total Time & Effort Required
• SLIM Software Equation Supports Effective Negotiation

Watch the video or continue reading to learn why the QSM SLIM methodology gets you the data and analytics to make software project commitments with confidence.

Benefit: Provides Data Needed for Early Software Project Cost and Schedule Decisions

What you measure matters! Your data analysis is only as good as the data you are collecting. As a project manager and process improvement consultant, I was so excited when I first learned about QSM's project tracking software, SLIM-Control^®, because product size, quality, and custom metrics are the best metrics to show the true project status.

Mind you, this discovery took place a long time ago when project tracking was primarily limited to data on staff levels, cost, and duration. These measures provided indirect evidence that work was being done, but gave little insight into exactly what work was actually being done and when it would be completed. I remember a large project team at my company that got into hot water because they overran a fixed-priced project by $1 Million!  My process improvement team member said, "You don't overrun by $1 Million overnight!"  There were probably several issues that contributed to this colossal failure, but certainly one was the lack of visibility into the project status or health on a regular basis to help managers and teams identify potential problems and fix them before they became unsurmountable.

In most organizations, spreadsheets play a vital role for a variety of uses, from time keeping to budgeting to even estimating software development releases.  They offer a level of familiarity - most of us cut our technical teeth on spreadsheets from a young age and have grown with them as we advanced our careers.  When it comes to estimating software development, spreadsheets are a common “go-to,” but an estimation tool offers more flexibility, timely “what-if” changes and far less complexity for new and seasoned estimators alike.

Have you ever been in an organization in which the estimation spreadsheet was so complex and cumbersome that only a select few knew how to use it?  This leaves an organization vulnerable to perhaps a single link of institutional knowledge upon which they are making vital business decisions.  And if that one project manager, analyst or architect leaves the organization, switches roles, or retires, what then?  Even if they go on vacation for 2 weeks, you’re left with a spreadsheet that may have an impossible learning curve for anyone else hence delaying or possibly negating the estimates being created at all.

In agile development, it's not unusual for software teams to have a fixed schedule or budget before any work begins. This is great information for stakeholders, but what if those targets are unrealistic? What if there were a way to evaluate trade-offs early in the decision-making process, before any detailed planning occurs?

With a top-down estimation tool like QSM's SLIM-Estimate, your scrum teams can quickly determine how much functionality they can deliver in a planned release schedule. If that target schedule turns out to be unrealistic, you can leverage SLIM-Estimate's time-tested models to calculate the impact of trade-offs. What happens if you add more people to the project? If the schedule is non-negotiable, how much functionality can you deliver in that period of time? SLIM-Estimate provides you with visualizations that are powerful when presenting to senior-level management and stakeholders. Plot your estimates against relevant agile trendlines from QSM's database of over 13,000 projects (the largest of its kind) and you can see how your estimates check out against the industry.

The video above shows how to use this powerful tool to generate defensible agile estimates you can present to stakeholders early in the planning process. Having data-driven information like this at your fingertips will allow you to plan and negotiate, and maybe even avoid disaster.

Early project decisions, when not much is known, are easily the hardest. They're also often the most critical. Maybe you've found yourself in a position where you need to communicate to stakeholders what your work is going to cost and how long it will take to deliver. Feeling the pressure to deliver, you might have to make decisions based on gut feel instead of past performance. This can lead to setting unrealistic targets and often results in projects going late or over budget. 

At QSM, this is when we recommend turning to historical data. Whether it's your own data or trendlines from the 13,000 validated projects in the QSM industry database, leveraging actual completed projects can make your estimates more reliable. 

Believe it or not, collecting your own project history isn't as difficult as it sounds. We recommend capturing just a few basic metrics: Functionality Delivered, Total Effort, and Total Duration. Once you have this information, you can calculate a Productivity Index, which is the measure of productivity for the overall project or release. Then all of these metrics can be leveraged by any of the other project lifecycle tools in the SLIM-Suite for estimating, tracking, and benchmarking.

In the video above, you can see how easy it is to gather your own completed projects to use early in the planning process and determine if your estimates are reasonable or not. This helps you understand the big picture before you make any important project or portfolio decisions.