These metrics closely relate to each other. For example, the number of deals in your funnel matters only if you know what percentage of your deals you win on average. The average size of a deal impacts the amount of deals you should be closing in order to hit your revenue goal. And sales velocity helps you understand how much of your time can and should go towards each quality deal, so you can manage your days effectively.
Process bottlenecks and hindrances. You might find, for example, that the proposal stage regularly delays the sales process by a week due to the need for custom quotes. Armed with that information, you can search for solutions that can automate how you produce project estimates. Alternatively, you may discover that some prospects are unengaged with the collateral you share at the lead generation stage. In this case, trial new marketing assets to see how well they respond and if they are more likely to convert into opportunities won later. 
In brief, we are inclined to go along with someone’s suggestion if we think that person is a credible expert (authority), if we regard him or her as a trusted friend (liking), if we feel we owe them one (reciprocity), or if doing so will be consistent with our beliefs or prior commitments (consistency). We are also inclined to make choices that we think are popular (consensus [social proof]), and that will net us a scarce commodity (scarcity).

sales funnel template

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