Why are companies rarely successful in reducing inventory or customer receivables?

Debtors and inventory in general depends on the business cycle. Many struggle to find a balance between sales and cash flow which results in piling up of recievables and inventory. Many struggle to maintain customer relationship vs sales vs cash flow and end up in huge recievables

Thanks for invitation,

In a very precise wording:

Reducing Inventory: is an indication of the highly effective and efficiency of the "Marketing and Sales strategy" , of the institution's excellent products.

Reducing Customer  Receivables: is an indication of an excellent of 'Credit and Collection policies", that are applied by the organization.

As a matter of fact, both are expressing an excellent institution's management style.