For me the difference lies in 'developing' and 'to develop' 1- You need to understand how consumers are selecting your products if you are /to develop/ packaging that is relevant. This suggests development has not yet started, so this company needs to ensure that they understand their consumers' choices before they start their packaging. 2- You need to understand how consumers are selecting your products if you are /developing/ packaging that is relevant. It could mean the same as the above, that they need to understand their customers first, but it could also mean that this developing is an ongoing process (i.e. that it has already started) and that they are not doing a very good job at selecting relevant packaging.

I would just use this sentence if it works for your intent. You need to understand how consumer(s) select your products in order to develop packaging that is relevant. Another example would be: You need to create product packaging that aides the consumer in selecting your product over similar products in each market area. A tidbit for you that is relative to the subject, Several manufacturers make several mistakes in their translations into many languages and as a result it can make their product quality seem cheap or even a fake. This is prevalent in many markets and is a key area that needs improvement.

I beg my pardon, i am not able to understand you sentence properly.

yes