When you are more concerned about having the work done with high quality, lower cost, fast turn-around than training the young people in your team, especially when your project involves some of the more complex and challenging bioinformatics ingredients, and/or requires custom development that goes beyond the level of basic bioinformatics work, then the scale is tilted towards the outsourcing option.
The bioinformatics work is naturally the most easily outsource-able among all components of your research project, because it deals with digital data that can often be transferred back and forth through the Internet without anything physical being shipped. This is in sharp contrast to other components of your project that involve biological samples and/or heavy or specialized experimental equipment or devices, which often makes the outsourcing option more cumbersome and less appealing.
It may be counter-intuitive that using external bioinformatics experts’ help can actually lead to saving in both your time and funding. This topic was discussed in this piece at AccuraScience’s web site, and I will not go deeply into it here.