While I have not invested in Bitconnect I figured I'd chime in as to why I haven't. For me personally it appears to be a Ponzi Scheme in that the guaranteed interest makes you want to hopefully reinvest and then as you do take money off they offset with new investors moving in so you are potentially paid back from their investment. I've seen no evidence of their trading bots nor have I seen a published white paper.
yeah thats the argument that i have read about, but does it matter ? i mean the white papper>
Just as @rumblestiltskin pointed out white papers give you the proper idea of how a project is aiming to achieve their goals. By not releasing anything it creates the appearance they are either not being honest with what's going on behind the scenes or are not competent enough to deliver such a simple qualifier.
The white paper is important to help understand what this currency actually does. If this is a scam or a poorly developed cryptocurrency then it would be smart to not explain the inner working of the network. If it is not a scam and does work the way they say, then the lack of white paper will prevent people from trusting this crypto and therefore not invest. This may in the end cause it's failure due to lack of growth.
Yes it absolutely matters. It is a way to scam money out of people who are already poor.